refactor(ui): adopt Astryx disclosures

[Astro-Han]

Summary

Refs #1565 (Slice 8, flat PR A).

Moves every disclosure owned by chat-turn.tsx, tool-activity.tsx, and task-ledger-panel.tsx directly onto @astryxdesign/core Collapsible. Maka retains only product state: manual tool expansion survives streaming/status rerenders, permission prompts auto-open, deep thinking starts collapsed and follows live content only while open, error diagnostics remain redacted and bounded, and the task ledger keeps its tree ordering and recent-terminal count.

This is one ownership boundary: it migrates all remaining consumers of Maka's shared Collapsible and removes the public/shared primitives that consequently have no real consumers. It does not touch model pickers, composer model controls, General Settings, or their stories/tests/styles.

Deleted surface:

• Maka's primitives/collapsible.tsx implementation and barrel exports
• the unused Accordion implementation, exports, and Story
• the unused Toggle, ToggleGroup, and Progress implementations, exports, and Stories
• their dead CSS hooks/comments and the retired Base UI source-shape disclosure contract

Intentional capability/appearance changes:

• Astryx owns the native button, chevron, focus ring, keyboard behavior, linked content region, and open-state chrome; Maka's duplicate quiet chevrons, focus framework, rotation hooks, and tool-card divider are gone.
• Maka's existing product open state gates heavy disclosure children. Collapsed tool output, processing timelines, deep thinking, and raw error diagnostics no longer build hidden trees; opening mounts them inside the Astryx-owned content region. This also lets live output auto-follow run after visible layout exists.

Verification

• rebased onto origin/main cf095e196
• npm run build — passed (all workspaces plus desktop renderer production build)
• npm run typecheck — passed after the dependency-ordered build refreshed cross-workspace declarations
• npm run format:check — passed
• npm run lint — passed
• npm test -w @maka/core — 1,254 passed
• npm test -w @maka/ui — 289 passed
• npm test -w @maka/desktop — 2,691 passed
• npm run build-storybook -w @maka/desktop — passed; DisclosureInteraction covers collapsed hit-testing, full-row trigger geometry, Enter expansion, visible content, and label/chevron alignment
• npx playwright test --config e2e/playwright.config.ts e2e/disclosure-output.spec.ts — 1 passed in a real Electron window; verifies Processing and its tool row do not mount collapsed output, expansion follows a static 160-line live stream to within 1px of the tail without a new chunk, and Space collapses/unmounts it
• MAKA_DISCLOSURE_E2E_SCREENSHOT=/tmp/maka-1565-disclosure-electron.png npx playwright test --config e2e/playwright.config.ts session-workbar.spec.ts — 2 passed earlier in this PR; verifies computed-style and keyboard ownership on the task-ledger journey. One live screenshot was captured locally; no screenshot baseline or generated image is committed.

Review focus

• Product state remains Maka-owned; generic disclosure mechanics are Astryx-owned with no compatibility wrapper or parallel state path.
• The task ledger already exposes role=tree/treeitem without focusable items, roving focus/aria-activedescendant, or APG Arrow/Home/End behavior. That existing accessibility gap is intentionally deferred to Slice 9; this PR only changes the surrounding recent-tasks disclosure. See the WAI-ARIA APG Tree View Pattern.
• Settings/MCP native <details> and BaseButton disclosures remain untouched for Slice 10.