Select dashboard tumbling pane sizes and enforce window correctness

[zzylol]

Stacked on #526. Planning and execution guards land together because accepting smaller panes without validating the read interval can return incomplete warm results.

Before this PR

Backend-local compilation accepted only lookback-sized Tumbling states, discarded concrete IDs during framework costing, and replaced the original lifecycle time scope with Unknown. Raw pane membership also used [start,end) although PromQL requires (start,end]. A production regression returned 10230 instead of 230 after wrongly including a left-boundary sample.

After this PR

• Accept separately quoted Tumbling pane sizes dividing the lookback. Preserve implementation IDs through Planner's complete-candidate estimate and install its selected pane width in state identity, precompute configuration and query bindings. Preserve original repeated QueryWorkload demand and time scope. Update Planner to current main abb2f20e27091ac0c60715dc42b9b59c75b3447c.
• Preserve legacy cadence compatibility; check actual evaluation alignment at serving time. Multi-pane reads reject partial, missing/open and interior missing panes before merging. Advancing lookbacks exclude old stored panes.
• Encode PromQL right-closed membership in raw state parameters/fingerprints. Shift only pane assignment and closure timestamps, preserving original accumulator sample timestamps.
• Exercise production RemoteWrite → control-plane planning/install → SUM/COUNT/ratio DAG → instant/range reads with selected 5s panes and advancing 10s lookbacks, including samples exactly at both boundaries. No min/max-specific implementation.

Verification

• cargo test -p control_plane --lib: 660 passed.
• cargo test -p data_plane --lib -- --test-threads=1: 982 passed.
• cargo test -p data_plane --test asapquery_compatibility_process_e2e -- --test-threads=1: 3 passed.
• Regression tests first reproduced partial-pane acceptance and the boundary overcount, then passed with the fixes. Candidate cost changes select different installed sizes while preserving lookback.
• Updated an inherited stale summary-update assertion to test expressions outside the now-supported column/unit-weight contract.

Sparse panes without explicit completion evidence conservatively fall back. Logical window expiration does not imply immediate physical reclamation. Candidate costs remain provider supplied; this PR does not invent a measured cost formula. Collector deployments retain lookback-sized panes. This is correctness/conformance coverage, not the real o11ybench benefit report.

Developer contract and reproduction: docs/developer_docs/planning/repeated-dashboard-panes.md.