feat(studio): support private and shared Bot bindings

[PolarisCzh]

Studio currently omits bindingType, so adding a Bot through the UI always relies on the Runtime default. This change adds an advertised Shared/Private choice to Feishu and Lark binding, with Shared as the default when available. QR creation, QR retry and manual binding forward the selection; retries keep the original type locked.

The private description is intentionally concise: “私聊可召回同 Bot 的历史，包括群聊。” / “Private chats can recall this Bot’s history, including group chats.” Runtime authorization and recall isolation are unchanged.

• Missing, empty or unknown-only botBindingTypes retains the legacy UI and request body. Other providers remain unchanged; Lark keeps domain=lark.
• Reuses the existing Radio component and fieldset styling. Type selection resets with the Runtime/provider/add-panel lifecycle; existing accounts have no type editing control.
• Includes bilingual design/spec/user documentation and rebuilt packaged WebUI assets. No Python production, dependency, storage or deployment changes.

Validation:

• 15 new component cases; test-first run had 9 expected failures, then all 87 component tests passed.
• Related component/client regression: 116 passed.
• Full frontend suite: 1,389 Node tests + 118 Vitest tests passed.
• Changed executable line coverage: 100% (6/6), derived from Istanbul/Cobertura against the Git diff. Entire RuntimeChannels file: 94.71% lines.
• Production build, locale consistency (2 locales / 21 namespaces), packaged assets (113 files / 350 references), channel proxy tests (6 passed), pre-commit and whitespace checks passed.
• Real browser with mocked Runtime: private/shared selection, keyboard navigation, concise description, QR/manual/retry payloads, locked retry selection, legacy UI, empty/loading/error/retry. Actual tested viewport was 708px; the attempted 390px override did not take effect.

No live Feishu registration/cloud deployment or real IME input was performed. Existing component IME and duplicate-submit regression passed. Full Python regression was not run because Python production code is unchanged. Existing toolchain warnings remain. This PR was based on origin/main at edae5b58.

Design and verification: prd-spec/features/bot-binding-types/2026-10-16-bot-binding-types.md and its Chinese counterpart.

CI follow-up (2026-10-16): all six upstream workflow runs are action_required pending fork approval; no CI jobs have executed. The author account cannot approve them (GitHub returns 403, repository admin rights required). Re-ran the backend Sidecar gate locally: 289 tests passed and the coverage gate passed (96%). Frontend Sidecar gate: 22 tests passed, 100% lines / 94.44% branches. Full frontend suite and pre-commit passed again. These local results do not replace upstream CI approval or the Linux release-bundle smoke job. No code change was needed for the observed approval blocker.