feat: evolve the SPA into a portable drafting workbench

[TingTung93]

Summary

• separate product identity from Ask Sage provider branding and introduce provider-neutral portable contracts
• add capability probing and adapters for Ask Sage, GenAI.mil, OpenRouter, OpenAI-compatible APIs, and keyless local LLMs with native-tool or prompt fallback paths
• add one durable proposal, preview, approval, revision, recovery, and undo lifecycle for template sections, template paragraphs, freeform blocks, and freeform paragraphs
• add stable target identity, stale-target protection, explicit source scope, bounded relevance selection, citation validation, and provenance review
• unify direct controls, command palette, chat commands, and guarded keyboard shortcuts through one action controller
• improve responsive and accessible workspace behavior, clarify route ownership, and rebuild the tracked single-file release artifact

Why

The SPA had accumulated provider-specific assumptions and several disconnected drafting/editing surfaces. This change establishes a cohesive provider-neutral architecture and a review-first editing lifecycle that works consistently across cloud and local providers without silently mutating documents.

User impact

Users can configure a broader range of API providers, including local OpenAI-compatible models, inspect capability limitations, target precise document regions, control grounding sources, review citation provenance, recover interrupted work, and safely accept, reject, revise, or undo edits. Existing data identifiers and legacy routes remain compatible.

Validation

• npm run typecheck
• npm test — 102 files, 754 tests passed
• npm run build
• rebuilt release/index.html as the reviewed single-file artifact

Notes

• V2 owns project drafting.
• Documents remains the specialized existing-DOCX editing surface.
• Legacy ProjectDetail is maintenance-only and is not removed in this release.
• Provider behavior and data-suitability guidance are documented in the updated user and release documentation.

[chatgpt-codex-connector]

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[TingTung93]

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[chatgpt-codex-connector]

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