docs: describe encryption scope, PDF rendering and backups as they are

The README said everything is kept encrypted at rest, that allergies and
family history are encrypted records, that the doctor report is
generated client-side, that there is no telemetry of any kind, and that
S3 backups are switched on in the admin panel. Free text, documents,
questionnaire answers, AI-written text and credentials are encrypted;
measurement values, lab values, medication names, mood scores and the
allergy substance or family condition are not. The PDF is rendered on
the server. Off-host backups are configured through the BACKUP_*
variables, and the admin panel only shows their status. The server's own
outbound requests are named along with their switches.

.env.example now says it is a starter and points at
.env.production.example as the complete reference, which is the file CI
checks against the env manifest. The Withings client id and secret it
listed are not read from the environment at all; they are entered in
Settings.

.env.example

@@ -4,6 +4,9 @@
 # Copy this file to .env and fill in the values.
 #   $ cp .env.example .env
 #
+# This is a short starter. Every variable the app reads, with what it does,
+# is documented in .env.production.example.
+#
 # Required variables: DATABASE_URL or POSTGRES_PASSWORD,
 #                     ENCRYPTION_KEY, API_TOKEN_HMAC_KEY
 #
@@ -76,10 +79,9 @@ API_TOKEN_HMAC_KEY="REPLACE-WITH-OUTPUT-OF-openssl-rand-hex-32"
 # -----------------------------------------------------------------------------
 # Withings OAuth (optional — for automatic scale/BP/activity sync)
 # -----------------------------------------------------------------------------
-# Register an app at https://developer.withings.com/ and paste the credentials
-# here. Per-user OAuth credentials can also be configured in Settings.
-# WITHINGS_CLIENT_ID=""
-# WITHINGS_CLIENT_SECRET=""
+# Register an app at https://developer.withings.com/ and enter its client id
+# and secret in Settings -> Integrations -> Withings. There is no environment
+# variable for them; only the redirect override and webhook secret live here.
 # WITHINGS_REDIRECT_URI="https://healthlog.example.com/api/withings/callback"
 # WITHINGS_WEBHOOK_SECRET=""  # any random string — used to harden the webhook URL
 

README.md

@@ -42,7 +42,7 @@
 
 ## Why HealthLog
 
-HealthLog is a self-hosted health tracking app (PWA + native iOS client) that runs from a single `docker compose up` on a NAS, homelab, or small VPS. It brings weight, blood pressure, pulse, blood glucose, body composition, sleep, mood, menstrual cycle, and medications onto one timeline — synced from the devices you already own — and keeps everything encrypted at rest on hardware you control. No vendor cloud, no subscription, no telemetry.
+HealthLog is a self-hosted health tracking app (PWA + native iOS client) that runs from a single `docker compose up` on a NAS, homelab, or small VPS. It brings weight, blood pressure, pulse, blood glucose, body composition, sleep, mood, menstrual cycle, and medications onto one timeline, synced from the devices you already own, and keeps it in a Postgres database on hardware you control. No vendor cloud, no subscription, no usage telemetry. The few requests the server makes on its own (an update check, a password breach check, an IP geolocation lookup for logins) can each be switched off.
 
 HealthLog is a personal health record-keeping and wellness tool. It is not a medical device and does not diagnose, treat, cure, or prevent any disease — it helps you log, visualise, and export your own data, and leaves clinical judgement to a clinician.
 
@@ -52,14 +52,14 @@ Try the [live demo](https://demo.healthlog.dev) to see a working install — sig
 
 - **Every vital on one timeline.** Weight, blood pressure, pulse, glucose, body composition, sleep, SpO₂, respiratory rate, mood, and cycle tracking — charted with trends, moving averages, and clinical reference ranges (ESH 2023, ADA 2024), overridable with the targets your clinician set.
 - **Clinical signals, opt-in and additive.** Validated self-checks for mental wellbeing and sleep (WHO-5, PHQ-9, GAD-7, Sleep Condition Indicator — official questionnaire wording, calm crisis-resource handling), grip strength, a 0–10 pain score, waist and body measurements, and a longevity lab panel — each added through one signal registry, so a new signal wires into charts, correlations, the coach, the FHIR map, and the API at once.
-- **Records, structured.** Allergies and family history as encrypted structured records that flow into the doctor report, plus lab values you key in or scan from a printed report — OCR extracts the stated values, units, and dates for you to review and confirm before anything is saved. HealthLog transcribes what a report says; it never interprets or diagnoses from it. A vaccination record keeps a lifetime immunization log, doses grouped under the disease they protect against, and prints in the doctor report.
+- **Records, structured.** Allergies and family history as structured records that flow into the doctor report (reactions and notes are encrypted, the substance and condition names are not), plus lab values you key in or scan from a printed report — OCR extracts the stated values, units, and dates for you to review and confirm before anything is saved. HealthLog transcribes what a report says; it never interprets or diagnoses from it. A vaccination record keeps a lifetime immunization log, doses grouped under the disease they protect against, and prints in the doctor report.
 - **A document vault for the paper trail.** An opt-in module stores every letter, report, and scan encrypted at rest — PDFs and photos preview inline, Office and text files stay download-only, and nothing user-uploaded can ever execute in the app. One searchable timeline with type, condition, and year filters, drag-and-drop and paste-to-upload, bulk filing, undo-able delete with a 30-day grace, and per-file/per-account limits the operator tunes.
 - **Context that explains the numbers.** An opt-in environmental module folds weather, daylight, and temperature in as influence signals (winter darkness against mood, heat against blood pressure) using a home location you set, so a pattern has somewhere to point.
 - **Your devices, one server.** Withings, WHOOP, Oura and Polar sync over OAuth2, Google Health connects Fitbit and Pixel Watch through your own Google Cloud client, Nightscout streams CGM glucose, an Apple Health `export.zip` folds your full history in, and the native iOS app streams HealthKit live. A per-metric source priority decides which reading is canonical when wearables overlap.
 - **Medication tracking that tells the truth.** Flexible schedules (weekly injections, weekday-only, intervals, PRN, cyclic), a configurable intake window per dose, and a traceable dose history where every slot reads taken, late, skipped, or missed — the same ledger the compliance rate is computed from, so the percentage can never disagree with the timeline.
-- **AI insights you own.** Daily briefing, health scores, correlations, and a conversational coach grounded in your own measurements and interpreted against cited guideline reference bands — where a value sits and what that means in plain words, never a diagnosis. The coach proposes concrete if-then plans you accept or decline, and suppresses proactive check-ins when there's nothing genuine to say. Bring your own OpenAI or Anthropic key, or point at a local endpoint (Ollama, LM Studio, vLLM) so nothing leaves your network.
-- **Clinician-ready output.** A doctor-report PDF generated client-side, a read-only HL7 FHIR R4 API, and scoped, time-limited share links you revoke after the visit.
-- **Private by construction.** AES-256-GCM encryption at rest with zero-downtime key rotation, passkey login, server-side sessions, strict CSP — and no third-party tracking anywhere.
+- **AI insights you own.** Daily briefing, health scores, correlations, and a conversational coach grounded in your own measurements and interpreted against cited guideline reference bands — where a value sits and what that means in plain words, never a diagnosis. The coach proposes concrete if-then plans you accept or decline, and suppresses proactive check-ins when there's nothing genuine to say. Bring your own OpenAI or Anthropic key, or point at a local endpoint (Ollama, LM Studio, vLLM) so AI requests stay on your network.
+- **Clinician-ready output.** A doctor-report PDF rendered on your server, a read-only HL7 FHIR R4 API, and scoped, time-limited share links you revoke after the visit.
+- **Private by construction.** AES-256-GCM encryption at rest for notes and other free text, documents, questionnaire answers, AI-written text and credentials, with zero-downtime key rotation. Measurement values, lab values, medication names and mood scores are stored unencrypted in the database, so the database volume and its backups need the same protection as the host. Passkey login, server-side sessions, strict CSP, and no third-party tracking anywhere.
 - **Built to be lived in.** Installable PWA with offline support, medication reminders over APNs, Telegram, ntfy, and Web Push, a sub-second dashboard on years of imported history — in English, German, Spanish, French, Italian, Polish, and Korean end to end.
 
 The full feature tour, integration guides, and API reference live at [docs.healthlog.dev](https://docs.healthlog.dev).
@@ -97,7 +97,7 @@ NAS and homelab users have ready-made paths: [Unraid Community Applications](doc
 
 ## Self-hosting
 
-One container hosts both the web server and the job worker by default; split them via `HEALTHLOG_PROCESS_TYPE=web|worker` for horizontal scale. Encrypted daily backups to any S3-compatible bucket are opt-in via the admin panel, new users join by invite link or QR code, and the stack works out of the box behind Caddy, Traefik, Nginx, or [Coolify](https://coolify.io/).
+One container hosts both the web server and the job worker by default; split them via `HEALTHLOG_PROCESS_TYPE=web|worker` for horizontal scale. Encrypted nightly backups to any S3-compatible bucket are opt-in through five `BACKUP_*` environment variables (the admin panel shows their status), new users join by invite link or QR code, and the stack works out of the box behind Caddy, Traefik, Nginx, or [Coolify](https://coolify.io/).
 
 HealthLog ships releases roughly weekly. Pin a tag, back up before upgrades, and skim the [CHANGELOG](CHANGELOG.md) before pulling `latest`. The operator manual — reverse proxy, migrations, encryption-key rotation, backup and restore — lives at [docs.healthlog.dev](https://docs.healthlog.dev).