Add Task-scoped plugin tabs to the Task drawer

[ukyovfx]

Problem

• The Task drawer has no plugin extension point, so the Files Plugin cannot stay inside the selected Shot/Asset Task workflow.
• Project plugin discovery cannot distinguish Task tabs from manager-only Production settings.

Solution

• Add Task-detail plugin tabs that receive the current Task context and preserve the drawer navigation state.
• Separate Task plugin and Production-admin discovery flags, with role-gated Production page navigation and same-origin theme/locale preferences.

[ukyovfx]

Verification at exact Draft head e20b9278a8b08594c75044aa8845a9a253e48ed9 (base main 619ff986b7c3e767eb7ba1001e05c0609edf2841): focused Task extension/context/preferences/store and TaskInfo tests passed, 116 tests total; Vite build passed; changed-file ESLint passed with the Prettier CRLF rule disabled for this Windows checkout, and git diff --check passed. Normal ESLint reports CRLF/Prettier line-ending diagnostics on this Windows checkout, not other lint findings. No checks are currently reported by GitHub. This is a frontend source candidate; installed native Task-drawer UAT against pinned Kitsu 1.0.70/Zou 1.0.94 has not been run, and no host was upgraded.

[ukyovfx]

Cross-repository UAT status (2026-10-17): PR #2276 exact HEAD e20b927 and PR #1288 exact HEAD f4a3ab98155aaf920a4dee492609e9363c0dc5ea are clean, open Drafts. The Task extension hook and Zou persisted Task/admin flags are present; no Kitsu/Zou host container currently runs. Available Docker candidate is a Plugin test-runner image, not a host. Authenticated Task drawer UAT remains blocked until a new isolated stack is assembled from these exact heads with the Plugin Task flag and synthetic host data. Existing UAT containers/volumes were preserved. No checks reported on these PR branches.

[frankrousseau]

Thank you for the contribution. We have to think about it before merging it.