De-brand the Agents "aquarium" — LevelCode chevron fish, brand-gradient species

The last reachable Microsoft mark in the shipped app. The Agents-window easter
egg (sessions.developerJoy.enabled) rendered its swimming "fish" as the literal
VS Code logo silhouette — vscodeLogoPath.ts even says so ("VS Code logo
silhouette path, extracted from …/vscode-icon.svg") — tinted with VS Code's
three RELEASE-CHANNEL colors (#007ACC / #24bfa5 / #E04F00). So Microsoft's logo,
in Microsoft's palette, animated across our product.

Keep the joy, make it ours: the LevelCode double chevron in our brand-gradient
stops (#6a3fe0 / #7069ff / #4fb2ff).

All CONTENT swaps in de-brand.mjs — no core patch needed (the patch stays at 11
files). Notes:
- the path `from` is a RegExp, so an upstream tweak to the silhouette re-matches
  and re-swaps instead of silently leaving the VS Code logo in place;
- the mark is FILLED (each fish is drawn as clipped vertical slices — a stroke
  would shred into segments) and spans BODY_X_START..BODY_X_END (5..90) so no
  head/tail strip is empty;
- it's two OVERLAPPING subpaths → fill-rule flipped evenodd→nonzero, else the
  overlap is knocked out as a hole.
Upstream identifiers (vscodeLogoPath.ts, VSCODE_LOGO_PATH, FishSpecies.Insiders)
are left alone — internal, never user-visible.

Also documents the letterpress watermark as NOT a de-brand issue: it's a generic
editor glyph (sidebar + text lines), no VS Code logo/wordmark/colour.

de-brand.mjs idempotent (2nd run: 0 changes); npm run compile-client → 0 errors.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: ndemianc

docs/CORE-PATCHES.md

@@ -95,7 +95,24 @@ regex/callback: link text is `[^\[\]\r\n]+` (can't span an `= [` array bracket t
 **`.d.ts` are included on purpose** — `monaco.d.ts` copies JSDoc (incl. these links) verbatim from the
 editor source, and the build fails ("monaco.d.ts is no longer up to date") unless both sides are stripped.
 
+**Also pass 1 — the aquarium easter egg (not a *name* swap).** `sessions/contrib/aquarium/**` renders the
+Agents-window "fish" as live SVG: upstream they are the **VS Code logo silhouette** (`vscodeLogoPath.ts`)
+tinted with **VS Code's three release-channel colors** (`#007ACC` / `#24bfa5` / `#E04F00`). We keep the
+easter egg and make it ours — the LevelCode **double chevron** in our brand-gradient stops
+(`#6a3fe0` / `#7069ff` / `#4fb2ff`). Three things to know if you touch it:
+- The path `from` is a **RegExp** (`export const VSCODE_LOGO_PATH = '…';`) so an upstream tweak to the
+  silhouette can't silently leave Microsoft's logo in place — it still matches and re-swaps.
+- The mark is **filled, not stroked**, and sized to the symbol's `0 0 96 96` viewBox spanning
+  `BODY_X_START..BODY_X_END` (5..90) — each fish is drawn as clipped vertical slices, so a thin stroke
+  would shred into disconnected segments and a narrower path would leave the head/tail strips empty.
+- It is two **overlapping** subpaths, so `fill-rule` is flipped `evenodd`→`nonzero` (evenodd would knock
+  the overlap out as a hole). Upstream file/const names (`vscodeLogoPath.ts`, `VSCODE_LOGO_PATH`,
+  `FishSpecies.Insiders`…) are deliberately left alone — internal identifiers, never user-visible.
+
 - **KEPT** (intentional): `sessions/contrib/applyCommitsToParentRepo/.../applyChangesToParentRepo.ts` "Open in VS Code" — a real hand-off to *external* VS Code via the `vscode://` scheme. And the `{Locked=…}` NLS annotations (translator metadata, never user-visible) keep their MS URLs.
+- **NOT a de-brand issue** (checked, left alone): the empty-editor **letterpress watermark**
+  (`parts/editor/media/letterpress-*.svg`) — it renders a generic editor pane with a sidebar and text
+  lines. No VS Code logo, wordmark, or brand colour; replacing it would be taste, not de-branding.
 - **SKIPPED**: M13 quality-switch dialogs — dormant (no Insiders LevelCode build); rebranding would imply a false "Insiders LevelCode".
 - **EXCLUDED**: `platform/agentHost/**` — its ~631 "VS Code" hits are all `test/` files + vendored proprietary Copilot/MS SDK (stripped from the shipped app by `strip-proprietary.mjs`).
 

scripts/de-brand.mjs

@@ -43,6 +43,14 @@ const vscodeDir = process.argv[2] || join(repoRoot, "vscode");
 // display string (settings descriptions, notifications) — verified by diff review.
 const G = [["Visual Studio Code", "LevelCode"], ["VS Code", "LevelCode"]];
 
+// The LevelCode double-chevron mark (branding/icons/code-icon.svg) as a FILLED silhouette in the
+// aquarium symbol's `0 0 96 96` viewBox, spanning the sliced body region (x 5..90, see fish.ts
+// BODY_X_START/END). Two overlapping subpaths — they union only under fill-rule:nonzero (the rule
+// below flips it; evenodd would knock the overlap out as a hole). Filled, not stroked: each fish is
+// rendered as clipped vertical slices, and a thin stroke would shred into disconnected segments.
+const LEVELCODE_FISH_CHEVRON =
+  "M6 47L48 12L90 47L78 57L48 32L18 57ZM6 79L48 44L90 79L78 89L48 64L18 89Z";
+
 // Each rule: { f: <path under vscode/>, subs: [[from, to], ...], extra?: [[from, to], ...] }.
 // `subs === G` is a whole-file name sweep; otherwise it's a TARGETED rule (explicit strings) — used for
 // files that contain a "VS Code" which must STAY (e.g. a real external-VS-Code reference) or where
@@ -118,6 +126,26 @@ const RULES = [
     ['"Open VS Code"', '"Open LevelCode"'],
   ] },
 
+  // ---- Agents-window "aquarium" easter egg: the fish were literally the VS Code logo silhouette,
+  //      tinted with VS Code's three RELEASE-CHANNEL colors, swimming across our UI. Keep the joy,
+  //      make it ours — our double-chevron in the brand-gradient stops. Pure content swaps, no patch.
+  //      The path `from` is a REGEX so an upstream tweak to the silhouette can't silently leave
+  //      Microsoft's logo in place; it still re-matches (and the file/const names are upstream's). ----
+  { f: "src/vs/sessions/contrib/aquarium/browser/vscodeLogoPath.ts", subs: [
+    [/export const VSCODE_LOGO_PATH = '[^']*';/, `export const VSCODE_LOGO_PATH = '${LEVELCODE_FISH_CHEVRON}';`],
+    ["// VS Code logo silhouette path, extracted from sessions/contrib/chat/browser/media/vscode-icon.svg.",
+      "// [LevelCode] The LevelCode double-chevron mark (branding/icons/code-icon.svg) as a filled silhouette."],
+  ] },
+  { f: "src/vs/sessions/contrib/aquarium/browser/fish.ts", subs: [
+    ['/** The three VS Code release channel colors used as fish "species". */',
+      '/** [LevelCode] The three brand-gradient stops as fish "species" (upstream: VS Code release channels). */'],
+    ["[FishSpecies.Stable]: '#007ACC'", "[FishSpecies.Stable]: '#6a3fe0'"],
+    ["[FishSpecies.Insiders]: '#24bfa5'", "[FishSpecies.Insiders]: '#7069ff'"],
+    ["[FishSpecies.Exploration]: '#E04F00'", "[FishSpecies.Exploration]: '#4fb2ff'"],
+    // Our mark is two OVERLAPPING subpaths; evenodd would knock the overlap out as a hole.
+    ["logoPath.setAttribute('fill-rule', 'evenodd');", "logoPath.setAttribute('fill-rule', 'nonzero');"],
+  ] },
+
   // ---- WS-D pairing: the Agents "Open in VS Code" button OPENS real VS Code, so it must show the VS
   //      Code shield — not code-icon.svg, which LevelCode overwrites with its own mark. (KEEP note:
   //      sessions/contrib/applyCommitsToParentRepo/.../applyChangesToParentRepo.ts "Open in VS Code" is a