chore: release 1.0.0-rc.8

[aesslinger]

Bumps version to 1.0.0-rc.8 with four fixes since rc.7:

• fix: show real values without float noise and keep row matching #144 — float4/REAL display + WHERE cast
• feat: add numeric_precision/scale and seq_in_fk for DDL type fidelity (#142) #143 — numeric_precision/scale + seq_in_fk
• fix: prepend selected schema onto search_path instead of overwriting #145 — search_path prepend + snapshot (Improve schema search_path handling (overwrite → append/prepend) #51)
• fix: implement get_materialized_view_definition (#32) #146 — materialized view definition (Phase 2.8: Wire up stubbed batch/snapshot RPC methods #32) + relkind filter

See CHANGELOG.md for the full release notes. After merge, tag v1.0.0-rc.8 triggers the release workflow (build, CHANGELOG extraction, GitHub prerelease publish).