feat(documents): choose how the vault is laid out, and confirm every delete

The wrench beside Upload opens Settings, Appearance, Documents, the way
the illness journal offers its display options: preview cards or a
compact list, and months stacked as blocks or flowing across the full
width with the month name inline above the document that opens it. The
choice is stored per account in `users.documents_layout_json` behind
GET/PUT /api/documents/inbound/layout (preserve-when-absent, module
gated, the read delegable like the rest of the vault), carried in the
account-settings backup and cleared by the data wipe.

Deleting from the vault now always asks first. The bulk bar's Delete and
a focused card's Delete key both go through one confirmation on the page,
and the detail sheet's Delete opens its own; before, all three deleted on
the spot with only an undo toast behind them.

The selection bar is two tight lines: the count with an X at its right
edge, then one action row with Delete alone at the right in the
destructive style. Below 1024 px the verbs are icon-only at the 44 px tap
floor, so the row stays one line at 360 px. The bar carries the
selection-bar slot the Coach launcher already steps aside for.

docs/api/openapi.yaml

@@ -17386,6 +17386,46 @@ paths:
         "403": *a11
         "422": *a4
         "429": *a5
+  /api/documents/inbound/layout:
+    get:
+      tags:
+        - Documents
+      summary: Get the vault presentation
+      description: The resolved card/list view and month arrangement for the vault, with defaults filled in when nothing has
+        been chosen. Inside a shared record this answers the owner's choice.
+      responses:
+        "200":
+          description: The resolved presentation.
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/DocumentsLayoutEnvelope"
+        "401": *a1
+        "403": *a11
+        "422": *a4
+        "429": *a5
+    put:
+      tags:
+        - Documents
+      summary: Change the vault presentation
+      description: "Preserve-when-absent: a body carrying only `view` keeps the stored arrangement and vice versa. Returns the
+        full resolved presentation. Refused while acting inside somebody else's record."
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/DocumentsLayoutPutBody"
+      responses:
+        "200":
+          description: The presentation as stored.
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/DocumentsLayoutSavedEnvelope"
+        "401": *a1
+        "422": *a4
+        "429": *a5
   /api/documents/inbound/bulk:
     post:
       tags:
@@ -31275,6 +31315,26 @@ components:
       additionalProperties: false
       description: Partial edit of a family-history entry; an omitted key leaves the column untouched. A `null`
         `ageAtOnset`/`note` clears that field. Rejects unknown keys.
+    DocumentsLayoutPutBody:
+      type: object
+      properties:
+        version:
+          type: number
+          const: 1
+        view:
+          type: string
+          enum:
+            - cards
+            - list
+        arrangement:
+          type: string
+          enum:
+            - stacked
+            - flow
+      required:
+        - version
+      additionalProperties: false
+      description: Either field may be omitted; the stored value is kept for the one left out.
     DocumentBulkRequest:
       type: object
       properties:
@@ -36661,6 +36721,7 @@ components:
                 insightsLayoutJson: {}
                 medicationListLayoutJson: {}
                 moodTagLayoutJson: {}
+                documentsLayoutJson: {}
                 reportSelectionJson: {}
                 globalExcludedInjectionSites:
                   type: array
@@ -72136,6 +72197,65 @@ components:
         - assistAvailable
         - contentIndex
       additionalProperties: false
+    DocumentsLayoutEnvelope:
+      type: object
+      properties:
+        data:
+          $ref: "#/components/schemas/DocumentsLayout"
+        error:
+          type: "null"
+        meta:
+          type: object
+          properties:
+            requestId:
+              type: string
+          additionalProperties: false
+      required:
+        - data
+        - error
+      additionalProperties: false
+    DocumentsLayout:
+      type: object
+      properties:
+        version:
+          type: number
+          const: 1
+        view:
+          type: string
+          enum:
+            - cards
+            - list
+          description: '`cards` renders the preview-tile grid, `list` one compact row per document. Default "cards".'
+        arrangement:
+          type: string
+          enum:
+            - stacked
+            - flow
+          description: '`stacked` gives every month its own block; `flow` runs the documents across the full width and wraps, with
+            month names inline. Default "stacked".'
+      required:
+        - version
+        - view
+        - arrangement
+      additionalProperties: false
+      description: Per-user document vault presentation. Display-only; a client that does not render a vault ignores it.
+    DocumentsLayoutSavedEnvelope:
+      type: object
+      properties:
+        data:
+          $ref: "#/components/schemas/DocumentsLayout"
+        error:
+          type: "null"
+        meta:
+          type: object
+          properties:
+            requestId:
+              type: string
+          additionalProperties: false
+      required:
+        - data
+        - error
+      additionalProperties: false
     DocumentBulkEnvelope:
       type: object
       properties: