refactor: phase 2 tail — declare capabilities for 14 plugins

[datlechin]

Summary

Phase 2 tail. 14 plugins declare honest PluginCapabilities based on what they actually implement. Pattern proven by SQLite migration in PR #1117. NO ABI bump (additive, default impl in protocol extension).

Verification

• currentPluginKitVersion stays 9.
• No Info.plist TableProPluginKitVersion changed.
• No method signatures changed.
• No new requirements added to PluginDatabaseDriver.
• xcodebuild Debug builds clean.
• swiftlint clean on all 15 touched files.

Per-plugin (honest, code-verified)

SQL plugins (commit 062f32a):

Plugin	Capabilities
MySQL	parameterizedQueries, transactions, alterTableDDL, foreignKeyToggle, cancelQuery
PostgreSQL	parameterizedQueries, transactions, alterTableDDL, multiSchema, cancelQuery, batchExecute
Redshift	parameterizedQueries, transactions, multiSchema, cancelQuery, batchExecute
MSSQL	parameterizedQueries, transactions, alterTableDDL, multiSchema, cancelQuery, batchExecute
Oracle	transactions, alterTableDDL, multiSchema
ClickHouse	parameterizedQueries, alterTableDDL, cancelQuery
DuckDB	parameterizedQueries, transactions, alterTableDDL, multiSchema, cancelQuery
LibSQL	parameterizedQueries, alterTableDDL, foreignKeyToggle, truncateTable, cancelQuery

NoSQL plugins (commit b6cdda3):

Plugin	Capabilities
MongoDB	cancelQuery
Redis	transactions, truncateTable, cancelQuery
Cassandra	parameterizedQueries, materializedViews, alterTableDDL

Cloud plugins (commit dee1bfb):

Plugin	Capabilities
DynamoDB	parameterizedQueries, cancelQuery
BigQuery	alterTableDDL, truncateTable, multiSchema, cancelQuery
CloudflareD1	parameterizedQueries, alterTableDDL, foreignKeyToggle, truncateTable, cancelQuery
etcd	cancelQuery

Notable judgment calls

1. Oracle parameterizedQueries omitted — driver has no executeParameterized override, so it falls back to default substitution. Honest declaration; revisit when binding gets wired.
2. Etcd truncateTable omitted — truncateTableStatements has stale signature (table:cascade:) that does not satisfy current protocol (table:schema:cascade:). Worth a follow-up signature fix; out of scope for additive PR.
3. DynamoDB truncateTable omitted — truncateTableStatements explicitly returns nil.
4. Cassandra multiSchema omitted — keyspaces exposed via fetchDatabases, not fetchSchemas. supportsSchemas is false.
5. Postgres compaction — capabilities literal compacted to single line because file body crossed the 1100-line type_body warning threshold.
6. No maintenance flag — Postgres has supportedMaintenanceOperations (VACUUM/ANALYZE/REINDEX/CLUSTER) but the foundation OptionSet has no maintenance capability. Not invented.

Out of scope

• Adopting PluginProcedureFunctionSupport sub-protocol (no plugin currently has procedure/function fetch).
• Splitting optional methods into sub-protocols (PluginAlterDDL, PluginMaintenance).
• ABI bump to v10.

Test plan

• Build clean (verified)
• swiftlint clean (verified)
• Connect each database type, confirm core queries work
• If issue Sidebar: group tables, views, materialized views, procedures, and functions into separate sections #1038 (sidebar grouping) lands later, the capability flags are ready to gate new sections per plugin