feat(web): add Smart Actions UI — prompt client, SmartActionsPanel, prompts page
Phase 3 of Smart Actions Roadmap:
- Create web/src/lib/prompt-client.ts: typed API client for all prompt endpoints
- listPromptTemplates, getPromptTemplate, createPromptTemplate, deletePromptTemplate
- runPrompt, suggestTags, checkDuplicates, suggestLinks, getReadingTime
- compareNotes, mergeNotes, getKnowledgeGaps
- Add Smart Actions types to web/src/lib/types.ts:
- PromptTemplate, RunPromptInput, RunPromptOutput, SimilarNote, KnowledgeGap
- Create SmartActionsPanel component:
- Reading time display, tag suggestion with accept/dismiss
- Category filter tabs, 2-column template grid
- One-click prompt execution with loading state
- Inline result display with copy/dismiss
- Create /prompts template library page:
- Browse built-in + custom templates with category filter
- Grid layout with input/output type badges
- Delete custom templates
- Wire SmartActionsPanel into note detail sidebar (above MetadataPanel)
- Add 'Prompts' nav item to Sidebar (Sparkles icon)
- Web typecheck passes, all 131 backend tests pass
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