feat(analytics): report read failures by error notification instead of inline text

[dearsimanovich-epam]

Description:

Analytics reported a failed read by writing a fixed English sentence into the page it was rendering — the same class of event that every other console surface reports through an error notification. Those sentences also said less than the app already knew: the service's errorHeader, errorMessage and requestId were read by BaseApi and then discarded, because the read methods returned T | null, so an operator had no request id to quote at the team running the service. And because the text was inserted into the page's own column flow, it shifted the grid down on arrival and back up on the next successful read.

Analytics read failures now travel as ServerActionResponse envelopes and are reported by error notification in the service's own words, falling back to the existing fixed string only where the service supplied none.

Key Changes:

• apps/ai-dial-admin/src/server/analytics/analytics-data-api.ts — all 13 read methods move from T | null to ServerActionResponse<T>, so the error envelope survives the call
• apps/ai-dial-admin/src/hooks/use-read-failure-notification.ts — new shared hook that raises the error notification from a failed read envelope
• apps/ai-dial-admin/src/components/Analytics/ConversationsTrace/Detail/Inspector/use-hop-read-report.ts — the inspector's own client-side reads report through the same path
• apps/ai-dial-admin/src/models/analytics/pipeline.ts — PipelineReadResult retired; a refusal is now read off status === 403
• Evaluators, Pipelines, ConversationsTrace, Tables and Queries pages and views — nine inline failure texts removed, server actions and callers updated for the envelope shape
• openspec/specs/analytics/ — specs synced: 1 requirement added, 11 modified across 5 capabilities; change archived under openspec/changes/archive/2026-09-15-move-analytics-load-errors-to-notifications/ keeping only proposal.md and design.md per the Analytics retention rule

New Components:

• useReadFailureNotification — shared hook turning a failed read envelope into an error notification carrying the service's header, message and request id
• useHopReadReport — the ConversationsTrace inspector's wrapper over that hook for its own client-side hop reads

Breaking Changes:

• AnalyticsDataApi's 13 read methods return ServerActionResponse<T> instead of T | null; every caller in this repo is updated in the same commit.
• PipelineReadResult is removed — callers read a refusal off status === 403.

Checklist:

• the pull request name complies with Conventional Commits
• the pull request name ends with (Issue #<ticket>) (comma-separated list of issues)

🤖 Generated with Claude Code