docs(ui): codify universal interaction patterns

docs/FRONTEND_LAYOUT_PRINCIPLES.md

@@ -23,6 +23,10 @@ Principles:
   panels, calendar list panels, or mailbox folder panels.
 - Keep collection navigation and collection-level actions close to the relevant
   pane header.
+- In a list-detail workspace such as Scheduling, keep related lists stacked in
+  the left pane and use the remaining main pane for view/create/edit. A single
+  Add action stays in the relevant list-pane header and opens the common main
+  editor; it does not create an additional menu or launcher.
 - Use bounded widths for navigation/list panes and let the main detail/content
   pane take the remaining space.
 - Keep filtering controls inside the pane they affect.
@@ -63,3 +67,11 @@ components directly.
 
 When a module-specific component becomes generally useful, promote it to core
 with a parameterized API before reusing it elsewhere.
+
+Non-self-explanatory fields use Core `FieldLabel`; documented omissions must
+name their accessible-label source. Explicit Discard and dirty navigation use
+the same Core unsaved-changes dialog. Table action sets retain unavailable row
+actions as disabled controls and reserve empty-state slots so Add remains
+aligned. Use central feedback/dialog components; `window.alert` is not an
+authorized product surface unless a product-owner-approved exception is first
+recorded in the Core decision ledger.

docs/INTERFACE_PATTERN_LANGUAGE.md

@@ -110,7 +110,10 @@ one.
   upper-right of the page heading. `Discard` comes before `Save …`, with the
   primary save action at the far right. Keep both controls in the same place
   across validation, loading, and saved states; guard unsaved work when the
-  user discards or navigates away.
+  user discards or navigates away. Explicit Discard and dirty in-application
+  navigation use the same central unsaved-changes dialog and registered
+  save/discard callbacks. A browser-controlled tab/window unload warning is the
+  only unavoidable different surface.
 - A page or panel has one visually primary action for its current state. Put
   secondary actions beside it. Separate destructive actions and name their real
   effect.
@@ -125,10 +128,16 @@ one.
 - Row actions in tables are icon-only controls in a stable rightmost action
   column. Order them by intent: inspect/open, edit, copy/duplicate,
   transfer/share/download, retry/restore, then remove/delete last. Omit actions
-  that do not apply without closing the gap or changing the relative order.
-  Every icon has a translated accessible name and matching tooltip. Separate
-  destructive actions visually, and use a named confirmation/review surface
-  when the consequence cannot be understood from the icon and row context.
+  only when they are structurally irrelevant to the entire table. An action
+  that belongs to the table but is unavailable for one row remains in its
+  normal position and is disabled; when the reason is not obvious from row
+  state, provide it through the central focusable disabled-action explanation.
+  It does not disappear. Every icon has a translated accessible name and matching tooltip.
+  Separate destructive actions visually, and use a named confirmation/review
+  surface when the consequence cannot be understood from the icon and row
+  context. In an empty editable table, place Add in the same left-most action
+  slot it occupies in a populated row and reserve the remaining slots so the
+  column geometry does not move.
 - Transient feedback should not shift the workspace. Durable failures, partial
   results, and blockers remain attached to the affected item or operation.
 
@@ -136,7 +145,12 @@ one.
 
 - Keep the selected object's identity and material status visible while its
   detail changes.
-- Short field help sits with the label. Longer "Why?", policy source,
+- Every non-self-explanatory field uses the central `FieldLabel`; short field
+  help sits with that label. A field without `FieldLabel` is an explicit
+  documented omission whose register names the field, rationale, and accessible
+  label source. Users may hide inline help markers with their persisted
+  interface preference; the visible/accessibility label and validation remain.
+  Longer "Why?", policy source,
   diagnostics, or provenance belongs in an expandable area, detail panel, or
   review step.
 - Empty space is not an error. An empty state states what is empty, why that can
@@ -199,6 +213,11 @@ Errors should identify the affected object and whether saved state or external
 effects may already exist. Never expose raw exception text as the only user
 message.
 
+Use the central dialog, confirmation, alert, and attached-error components for
+feedback. `window.alert` and the global `alert` function are prohibited. A
+genuinely unavoidable exception requires explicit product-owner authorization
+and an entry in the Core alert exception register before implementation.
+
 ## State Contract
 
 Every surface implements the states it can reach; it does not render a blank
@@ -355,11 +374,18 @@ and appearance.
 The Scheduling request surface is the first explicit reference composition for
 these rules:
 
-- The `Scheduling requests` page heading owns one `Add` action.
-- The left panel is shown for the creation view; it is not a second permanent
-  creation launcher beside the request list.
+- The persistent left panel contains `My scheduling requests` and `Scheduling
+  requests for me` as two stacked lists. It preserves list context like mailbox
+  folders but does not invent folders.
+- The left pane's `Scheduling requests` heading owns one short `Add` action. It
+  opens a new request in the right pane without an extra menu or duplicate
+  launcher.
+- The right main pane is the stable view/create/edit surface. Selecting a list
+  item opens its details; Add opens the same editor composition used for edit.
 - `Basic information`, `Calendar integration`, `Candidate slots`, and
   `Participants` are logical sections rendered with the central `Card`.
+- Privacy and participation behavior is a separate settings `Card`; dependent
+  number/password fields are disclosed by their central `ToggleSwitch`.
 - Candidate slots and participants are row collections rendered with the
   central `DataGrid`, including its stable action column.
 - Calendar integration is a boolean choice rendered with the central
@@ -368,6 +394,10 @@ these rules:
   ordered row actions. An address-parsing text area is not the ordinary editor;
   parsing pasted address lists belongs only in an explicitly designed bulk
   import flow.
+- View mode shows participation statistics and only state-valid quick actions.
+  Scheduling owns those current domain actions; a future Workflow module may
+  coordinate them through stable action contracts but is not a runtime
+  dependency of the surface.
 
 Apply the underlying placement and component rules to equivalent collection and
 create/edit surfaces throughout the system; the Scheduling domain names are an