Pivot to text-first column-stack workspace + merge-with-review across AI artifacts

Workspace
- Pivot from "set of open panes" to a Finder-style miller column stack:
  TopBar / LeftSidebar / [section → entity → entity ...] / pinned text editor.
  openPanesStore is now an ordered Column[] with pushFrom / closeFrom /
  setStack; only one top-level section is rooted at a time.
- New entity column panes: Term, Block, Association, Constraint,
  Requirement, Finding. Click-through navigation truncates deeper
  columns automatically.
- LeftSidebar surfaces a pending-count chip per section (single-glance
  navigation cue) and spins its analyze ↻ via SVG Spinner whenever the
  LLM is working — including server-initiated runs caught by the runs
  poll, not just user-triggered ones.

Analyze pipeline + persistence
- Unified `concepts` pass (taxonomy + glossary in one LLM call) replaces
  the two-pass setup. Server still accepts ?section=taxonomy|glossary
  and normalizes them for back-compat.
- model / requirements / detection (assumptions, risks, inconsistencies)
  + cross-layer validation rules (X1–X4: stale term link, unlinked
  formalism, undefined linked term, prose-only term).
- Persistence: NarrativeDocument, ModelSnapshot, ChangelogEntry,
  TaxonomyTerm, RequirementEntry, Finding, AnalysisRun. Re-runs MERGE
  instead of replace: gentle update on existing items, suggested on new,
  deprecated on missing — same idiom for every artifact kind. User pins
  preserve "kept" decisions across re-analyses.
- Migrations: pivot_text_first, add_requirement_linked_term,
  term_review_state, review_state_for_reqs_and_findings,
  add_term_definition_pinned.

Concept ↔ ontology integration
- linkedTermId on Block / Association / Constraint / Requirement.
  PromoteToolbar lets the user formalize a concept inline: + Block /
  + Association / + Constraint / + Requirement, all routed through
  applyOps so undo/redo and SSE work for free.
- decideElement op for in-canvas keep/discard on review-pending model
  elements.

User-authored definitions
- TermColumn definition is click-to-edit. Save (Cmd-Enter / blur),
  Cancel (Esc), Reset to AI suggestion when pinned.
- definitionPinned flag on TaxonomyTerm: future Analyze runs leave the
  user's text alone. setTermDefinition repo function + POST
  /api/projects/[id]/terms/[termId]/definition endpoint.
- mergeTaxonomySuggestion + applyGlossaryDefinitions both pin-aware.

UX/UI
- StatusChip: single component for all state idioms (suggested,
  deprecated, accepted, dismissed, resolved, severity, validation code,
  confidence, warn). Replaces 5+ ad-hoc badge classes.
- PaneControls (PaneViewTabs + PaneFilterChip): separates view-mode
  toggles from filter chips so toggling Pending no longer flips you off
  the current view.
- PaneEmpty: unified empty-state with title + hint + action.
- PaneDrawer: collapsible groups for Pending / Discarded review; cards
  group as Kept (top) → Pending (bottom drawer) → Discarded (Findings
  only, hidden when empty). Restore action recovers dismissed/resolved
  findings.
- ConceptCard unifies Tree and A–Z views in Concepts; only Tree parents
  carry the chevron (no empty placeholder offset).
- Type + spacing tokens (--text-xs..xl, --space-1..6, --lh-tight/ui/
  prose, --radius-*) replace every ad-hoc value.
- Buttons standardized to body sans 500 (was a mishmash of mono / display).
- Card shells unified across Concepts / Requirements / Findings.

Cleanup
- Removed: LeftRail, FindingsPanel, IssuesPanel, SocratesDock,
  ProposalCard, SlashMenu, SlashExtension, slashSuggestion,
  CanvasHeader, TaxonomyPane, GlossaryPane, TermDetail (popover; now
  TermColumn).
- Section ids in openPanesStore: dropped taxonomy/glossary, added
  concepts. localStorage migration runs on hydrate.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/lib/llm/socrates.ts

@@ -195,6 +195,46 @@ export async function sendUserTurn(args: SendUserTurnArgs): Promise<SendUserTurn
   };
 }
 
+// ─── Anchored threads (contextual mini-Socrates per finding) ─────────────
+
+/** Find an existing thread anchored to `anchor` for this project, or create
+ *  one. Returns the thread id. */
+export async function getOrCreateAnchoredThread(
+  projectId: string,
+  anchor: string,
+  title?: string
+): Promise<string> {
+  const existing = await prisma.socratesThread.findFirst({
+    where: { projectId, anchorElementId: anchor },
+    orderBy: { updatedAt: "desc" },
+  });
+  if (existing) return existing.id;
+  const created = await prisma.socratesThread.create({
+    data: { projectId, anchorElementId: anchor, status: "open", title: title ?? null },
+  });
+  return created.id;
+}
+
+export async function listAnchoredThreadMessages(threadId: string) {
+  const rows = await prisma.socratesMessage.findMany({
+    where: { threadId },
+    orderBy: { createdAt: "asc" },
+    select: { id: true, role: true, content: true, createdAt: true },
+  });
+  return rows.map(r => {
+    let text = "";
+    let options: SocratesOption[] | undefined;
+    try {
+      const parsed = JSON.parse(r.content) as { text?: string; options?: SocratesOption[] };
+      text = parsed.text ?? "";
+      options = parsed.options;
+    } catch {
+      text = r.content;
+    }
+    return { id: r.id, role: r.role, text, options, createdAt: r.createdAt };
+  });
+}
+
 // ─── Helpers ─────────────────────────────────────────────────────────────
 
 function trimModel(model: SysMLModel): unknown {