feat(encounters): one suggestion rule for every filing moment

A document arriving in the vault and a lab panel being committed both ask the
same question — does this belong to a visit? — and the answer has to be the
same question asked once. The rule lives in one module with one exported
window constant: the caller's live DONE or PLANNED visits within seven days of
an anchor date, resolved into a verdict rather than a list.

One candidate pre-selects, visibly, with one undo. Two or more offer a picker
with nothing pre-selected: pre-selecting the first of two is what teaches a
person to stop reading suggestions, and the return type has no field on that
arm a caller could mistake for a choice. Zero offers nothing.

Cancelled visits and no-shows are not candidates. Neither happened, so neither
produced the letter or the panel being filed, and admitting them would widen
the set with rows that are wrong most of the time — which pushes the honest
single match into the picker branch.

The verdict is served over HTTP because all three moments live in the browser.
Handing the client a windowed list and letting it decide would put the rule in
two places, and the copy in the browser is the one nobody re-reads.

- suggest-window.ts with the window as an exported constant, not a literal
- GET /api/encounters/suggest, profile domain, reviewed into the frozen literal
- OpenAPI regenerated
- fixtures are relative to the run instant; a fixed date slides out of a
  relative window and rots the test into a false green

docs/api/openapi.yaml

@@ -9825,6 +9825,36 @@ paths:
         "403": *a6
         "422": *a3
         "429": *a4
+  /api/encounters/suggest:
+    get:
+      tags:
+        - Records
+      summary: Which visit does a record dated around this day belong to?
+      description: "Resolves the caller's live DONE or PLANNED visits within ±7 days of `anchor` into a verdict, so the three
+        capture moments that ask the question — a document arriving, a lab panel committed from an extraction, a lab
+        panel typed by hand — all read the same answer. `one` means pre-select it visibly with one undo; `many` means
+        offer a picker with NOTHING pre-selected, because pre-selecting the first of two teaches a person to stop
+        reading suggestions; `none` means offer nothing at all. Cancelled visits and no-shows are never candidates:
+        neither happened, so neither produced the record being filed. No AI provider is involved and none is required."
+      parameters:
+        - in: query
+          name: anchor
+          schema:
+            type: string
+            format: date-time
+            pattern: ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z|([+-](?:[01]\d|2[0-3]):[0-5]\d)))$
+          required: true
+      responses:
+        "200":
+          description: The verdict.
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/SuggestEncounterEnvelope"
+        "401": *a1
+        "403": *a6
+        "422": *a3
+        "429": *a4
   /api/encounters/{id}:
     get:
       tags:
@@ -34923,6 +34953,99 @@ components:
         - data
         - error
       additionalProperties: false
+    SuggestEncounterEnvelope:
+      type: object
+      properties:
+        data:
+          $ref: "#/components/schemas/EncounterSuggestion"
+        error:
+          type: "null"
+        meta:
+          type: object
+          properties:
+            requestId:
+              type: string
+          additionalProperties: false
+      required:
+        - data
+        - error
+      additionalProperties: false
+    EncounterSuggestion:
+      oneOf:
+        - type: object
+          properties:
+            kind:
+              type: string
+              const: one
+            encounter:
+              $ref: "#/components/schemas/EncounterSuggestionCandidate"
+          required:
+            - kind
+            - encounter
+          additionalProperties: false
+        - type: object
+          properties:
+            kind:
+              type: string
+              const: many
+            encounters:
+              type: array
+              items:
+                $ref: "#/components/schemas/EncounterSuggestionCandidate"
+          required:
+            - kind
+            - encounters
+          additionalProperties: false
+        - type: object
+          properties:
+            kind:
+              type: string
+              const: none
+          required:
+            - kind
+          additionalProperties: false
+      description: "The verdict, as a shape rather than a best guess. There is deliberately no field on the `many` arm a
+        client could read as a pre-selection: collapsing two candidates into one is the failure this union exists to
+        make impossible."
+      type: object
+    EncounterSuggestionCandidate:
+      type: object
+      properties:
+        id:
+          type: string
+        occurredAt:
+          type: string
+        status:
+          type: string
+          enum:
+            - PLANNED
+            - DONE
+            - CANCELLED
+            - NO_SHOW
+        kind:
+          type: string
+          enum:
+            - ROUTINE
+            - ACUTE
+            - SPECIALIST
+            - PREVENTIVE
+            - EMERGENCY
+            - HOSPITAL
+            - THERAPY
+            - OTHER
+        practitionerName:
+          anyOf:
+            - type: string
+            - type: "null"
+      required:
+        - id
+        - occurredAt
+        - status
+        - kind
+        - practitionerName
+      additionalProperties: false
+      description: One visit a record might belong to, resolved far enough to render a row without a second round trip.
+        `practitionerName` is null when the visit names no practice, which is an absence rather than a gap.
     GetEncounterEnvelope:
       type: object
       properties: