feat: build functional Endor start page and balance compact tabs

docs/ui-workspace-audit.md

@@ -4,9 +4,9 @@ This audit follows the full conversation, including later corrections. Implement
 
 | Requirement | Implementation | Evidence / limits |
 | --- | --- | --- |
-| One top row with native macOS controls | Transparent/full-size native title bar; reserved control space; 44 px tab strip | Actual Retina macOS windows viewed; native close/minimize/fullscreen controls retained |
+| One top row with native macOS controls | Transparent/full-size native title bar; reserved control space; 40 px tab strip | Actual Retina macOS windows viewed; native close/minimize/fullscreen controls retained |
 | Continuous left/top chrome | One neutral background; 56 px left rail; inset content panel | Actual main and detached windows viewed; no Tools label or rail launchers |
-| Larger symmetric round tabs, softer active state | Common capsule bounds, measured glyph centering, no hard active stroke | Native settled UI viewed; hover and selected use the same bounds |
+| Compact symmetric round tabs, softer active state | 208 px maximum width; equal 4 px vertical insets; matching icon/close slots; no hard active stroke | Native settled UI viewed; hover and selected use the same bounds |
 | + and startup default page | One startup request guarded against duplicate resume; + release-inside; Cmd/Ctrl+T | Immediately after restart: pages().count = 1. Two native Cmd+T actions produced three tabs |
 | New-tab motion, filled and unfilled | 200 ms cubic ease; new width grows from zero; existing bounds and + interpolate; scalar-only animation data | Real native new/close/fill operations completed; settled compression/overflow viewed. No frame-by-frame recording or Chrome timing comparison |
 | Overflow and scrolling | Separate + reservation; arrows, edge dwell and hit bounds share tab viewport | Native overflow reached; + in overflow increased VM count 7 → 8. Dragging out of + kept count at 7 |
@@ -15,7 +15,7 @@ This audit follows the full conversation, including later corrections. Implement
 | Four tools not default or permanently placed | No Tools menu, rail buttons or new-page tool directory; existing API/shortcut retained | Final default surfaces viewed without tool entries |
 | Source reading/selection/copy | Grapheme-boundary selection, no gutter in copy, select-all/copy, Shift navigation, drag edge scrolling | Native single-line drag/copy/paste verified earlier in this change. Final keyboard copy was re-run after the chrome-focus fix: drag-copy matched the complete selected line; four Shift+Right operations copied the expected four characters; select-all copied multiline source without a gutter. Drag edge behavior compiled; exhaustive combinations remain untested |
 | Clicking Console output must not jump to prompt/end | Input hit region restricted to actual prompt rows | Native reading/copy path verified earlier; no input hit over transcript-only area |
-| Default page reflects Endor | Objects, code and UI share identity; persistence/model connections explicitly described as work in progress | Referenced chats read: 01a16819-28c3-7ce0-9423-0ffaa19402ce and 01a1689b-77d8-75a2-ba9e-b2fa3dce654e; actual native start surface viewed |
+| Default page reflects Endor | Real Endor Page with creation, shared-object and composition actions; no persistence/model backend claims | Referenced chats read: 01a16819-28c3-7ce0-9423-0ffaa19402ce and 01a1689b-77d8-75a2-ba9e-b2fa3dce654e; actual native start surface viewed |
 | Sensible source organization | Runtime/API tests separated; four page view modules; shared painter/selection; native tool Page factory; motion module | All-target Clippy compiled production and test sources. Runtime host reduced from ~7000 to ~1380 lines |
 | Protect existing work | examples/README.md and examples/workspace.endor excluded; vendor/Aster untouched | git status checked before staging |
 | Verification restrictions | fmt, all-target Clippy -D warnings, release build and manual native/API checks | No cargo test, smoke script, Docker, dependency test install or CI polling |
@@ -44,3 +44,38 @@ After the fix, direct system clipboard comparisons (without printing clipboard c
 ## Local delivery state
 
 Implementation commits: 3220544 (runtime test-source separation), 656522e (managed workspace/chrome implementation), d3165b1 (behavior and requirement audit), followed by the chrome-focus fix commit. A push to origin/main was attempted once and rejected by automatic approval review because explicit authorization for this default-branch remote mutation was required. No alternative push route was attempted. The remote remains unchanged pending the user's approval.
+
+
+## Functional start-page revision
+
+The previous Rust-painted introduction was removed. `ui_bridge/start_page.endor`
+now defines a managed Page subclass with native layout alignment, real buttons,
+a shared-state counter and a composed-Blocks example. Its private module globals
+do not overwrite user REPL bindings. The same factory is available as `ui.newTab()`;
+legacy `ui.developerTools("New tab")` delegates to it. No developer-tool entry is
+shown on the start page.
+
+Native startup checks caught unsupported comparison syntax and unimplemented
+arithmetic bytecode in initial layout drafts. Those drafts were replaced with
+existing Page/Row measurement and native `mainAlign`, without changing Aster.
+A subsequent layout check caught unbounded child-height centering; sizing now
+belongs to the root Page, which receives the actual content constraints.
+These failures were corrected locally, and are not counted as passing checks.
+
+
+Final native checks for this revision: all three start-page buttons opened their
+corresponding managed Pages; the blank-page return action activated its original
+home Page; one native counter click changed both views from 0 to 1. Overflow
+navigation was visible while these Pages were added. A direct `ui.newTab()` call
+increased the live Page count from 4 to 5, confirming one Page per factory call.
+The final window was also being operated by the user (reported by the UI tool),
+so the pre-existing four tabs are not treated as a clean-start count measurement.
+No additional restart was done after that interaction. The earlier isolated
+startup count of one remains evidence for the guarded startup path; the new
+factory's single-call count was checked separately.
+
+Formatting, all-target offline Clippy with warnings denied, the release macOS
+bundle and diff whitespace checks passed. No test suite or smoke script was run.
+All earlier requirements were reviewed against the table above; isolated Chrome
+motion comparison and the explicitly listed cross-window/DPI verification gaps
+remain unverified, rather than being marked complete.