CI: execute every report view against seeded rows (#1669)

[erikdarlingdata]

Closes #1669 — the follow-through on the #1635/#1666 bug class: views that compile and exist but only fail (or corrupt) when rows flow through the projection. ci_validate_installation.sql checks report.* by OBJECT_ID alone.

What's added

• .github/sql/ci_seed_report_sources.sql — one guarded representative row per collect/config table, generated from the installed schema (NOT NULL/non-identity/non-computed columns get type-appropriate values; nullable columns stay NULL so those branches execute; compressed-LOB columns get real COMPRESS() payloads; timestamps land 5 minutes back so "today"/"last hour" windows include them). The three change-history tables get hand-authored correlated PAIRS (trace flag OFF→ON, server knob changed, database setting changed) so the LAG/toggle views emit actual rows. Every insert is guarded on the table being empty — re-runnable anywhere, inert on real data.
• .github/sql/ci_execute_report_views.sql — enumerates sys.views in the report schema at run time and materializes each with SELECT * INTO — COUNT(*) would let the optimizer prune the projection and skip exactly the per-row conversions this exists to catch. Failures are collected and re-thrown as one error listing every broken view; sqlcmd -b turns that into a red job. Dynamic enumeration covers future views automatically and tolerates the collection-time-built report.query_snapshots pair being absent on a fresh install.
• .github/sql/ci_generate_seed_rows.sql — dev tool (not run by CI) to regenerate the seed section after schema changes.
• sql-validation.yml — two new steps after installation validation, across the full 2017/2019/2022/2025 matrix. The workflow paths-filter includes .github/sql/** and the workflow file, so this PR's own checks run the new sweep end-to-end on all four versions.

Validation

• Local full install on a real SQL Server 2022 (every install script 01–51 minus agent/test): seed clean, sweep 41 views executed, 0 failed.
• Detection power: a planted view with a per-row-only Msg 245 (CONVERT(int, N'ci') over a seeded column — the [BUG] report.trace_flag_changes fails with bit-to-nvarchar conversion error #1635 shape, invisible over zero rows) flips the sweep to 1 failed with the view named, and the final THROW propagates.
• Known limit, stated in the script header: silent-semantic bugs like [BUG] report.daily_summary_v2.metric_value renders worst_query_hash as garbled text #1666's (valid execution, wrong value) still need targeted checks — this catches the throw-on-execute class.

🤖 Generated with Claude Code

[erikdarlingdata]

SQL Server 2016 coverage (the min-supported version the matrix can't include — SQL Server on Linux starts at 2017, so no 2016 container image exists):

Ran the identical sequence manually against the local SQL2016 box (13.0.6300), scratch database, fixture PerformanceMonitor DB untouched:

• full install surface (01–51 minus agent/test scripts): clean
• ci_seed_report_sources.sql: clean, twice
• ci_execute_report_views.sql: 41 views executed, 0 failed

The matrix now carries a comment recording why 2016 is absent and that it's validated manually as part of release testing.