feat(api): say why a module's surfaces are not there, not only that they are not

`GET /api/auth/me` publishes a boolean per module, and three different
situations collapse into the same `false`: the record has the module switched
off, the active grant's sections do not open it, or the operator switched it
off for the whole instance. A client holding the boolean has to guess between
them, so the empty state either says nothing or says something that may be
untrue -- offering a delegate a switch that is not theirs to reach, or telling
an account holder to turn on a module the operator removed.

`moduleAccess` carries the reason beside the booleans, which keep their exact
meaning: `enabled`, `disabled`, `not_granted`, `unavailable`, resolved
outside-in so the reason published is the one nothing further in can change.
`modules[key]` stays exactly `moduleAccess[key] === "enabled"` for every key,
and the two halves are built independently -- the boolean still runs through
`maskModulesToSections` -- so the test of that pairing is an assertion rather
than a restatement of a derivation. It is checked on the pure builder across a
matrix of grants, records and operator blobs, and again on the real route for a
scoped delegate, an unscoped one, and an operator-disabled module.

Both ends in one change, because a payload field with no reader is the failure
this repository keeps rediscovering. The reader is `ModuleDisabledNotice`, the
shared module-off empty state the empty-states audit asks for: it names the
reason in the reader's own language and offers the enable control only when the
record's own switch is what is off, since neither of the other two is fixable
from that page. The nutrients page adopts it and drops its bespoke block, which
had been handing every delegate a button that would refuse them.

Registered in the OpenAPI registry as `ModuleAccessMap` and carried on the
account payload; the native contract gains a field and loses nothing, since a
Bearer request carries no switch and never reads `not_granted`.

docs/api/openapi.yaml

@@ -65763,6 +65763,8 @@ components:
           type: string
         accountAccess:
           $ref: "#/components/schemas/AccountAccess"
+        moduleAccess:
+          $ref: "#/components/schemas/ModuleAccessMap"
         recordSession:
           anyOf:
             - $ref: "#/components/schemas/RecordSessionState"
@@ -65771,6 +65773,7 @@ components:
         - id
         - username
         - accountAccess
+        - moduleAccess
         - recordSession
       additionalProperties: {}
       description: "The signed-in account: its identity, its preferences, and (since v1.36.0) what account sharing lets it do.
@@ -65780,7 +65783,9 @@ components:
         `cycleTrackingEnabled` describe the ACTIVE RECORD, since every surface they gate shows the record's data — and
         they are masked to the sections the active grant opens, so a scoped grant reads `false` for a module outside it
         rather than the record's true state. With no switch — which is every native request, since the Bearer transport
-        carries none — the two are the same account and nothing is masked."
+        carries none — the two are the same account and nothing is masked. `moduleAccess` says WHY each module is or is
+        not there — the record's own switch, the edge of the grant, or the operator's instance-wide one — beside the
+        `modules` booleans it never contradicts."
     AccountAccess:
       type: object
       properties:
@@ -65985,6 +65990,191 @@ components:
         be a second program deciding one person's access to a health record, and the two answer differently the first
         time an expiry or a revocation appears. Always present — an account nobody has shared with gets an empty list,
         not a missing field."
+    ModuleAccessMap:
+      type: object
+      properties:
+        cycle:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "cycle" module is or is not available here.
+        mood:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "mood" module is or is not available here.
+        sleep:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "sleep" module is or is not available here.
+        glucose:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "glucose" module is or is not available here.
+        workouts:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "workouts" module is or is not available here.
+        recovery:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "recovery" module is or is not available here.
+        labs:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "labs" module is or is not available here.
+        illness:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "illness" module is or is not available here.
+        achievements:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "achievements" module is or is not available here.
+        coach:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "coach" module is or is not available here.
+        insights:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "insights" module is or is not available here.
+        medications:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "medications" module is or is not available here.
+        doctorReport:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "doctorReport" module is or is not available here.
+        environment:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "environment" module is or is not available here.
+        mcp:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "mcp" module is or is not available here.
+        inboundDocuments:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "inboundDocuments" module is or is not available here.
+        mentalHealth:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "mentalHealth" module is or is not available here.
+        nutrients:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "nutrients" module is or is not available here.
+        vaccinations:
+          type: string
+          enum:
+            - enabled
+            - disabled
+            - not_granted
+            - unavailable
+          description: Why the "vaccinations" module is or is not available here.
+      required:
+        - cycle
+        - mood
+        - sleep
+        - glucose
+        - workouts
+        - recovery
+        - labs
+        - illness
+        - achievements
+        - coach
+        - insights
+        - medications
+        - doctorReport
+        - environment
+        - mcp
+        - inboundDocuments
+        - mentalHealth
+        - nutrients
+        - vaccinations
+      additionalProperties: false
+      description: "Why each toggleable module is or is not available for the record this session is inside. `enabled` — the
+        module is on and the client may paint it. `disabled` — the record has it switched off. `not_granted` — the
+        active grant's sections do not open the module's section, which also covers every module that reads across the
+        whole record (achievements, the assistant surfaces, the export, environment, the account's own MCP endpoint)
+        since no scoped grant opens one. `unavailable` — the operator switched the module off for the whole instance.
+        Precedence, highest first: `unavailable` > `not_granted` > `disabled` > `enabled`, so the reason published is
+        the one nothing further in can change. Own-record sessions and unscoped grants never produce `not_granted`.
+        Every key is present, and `modules[key] === (moduleAccess[key] === \"enabled\")` holds for every key — this
+        field adds a reason, never a different gate."
     RecordSessionState:
       type: object
       properties: