add commands for warming the overlay-base cache

[ginsbach]

• This fixes https://github.com/github/codeql-core/issues/5026 and is an important part of https://github.com/github/codeql-core/issues/5005.

This PR adds a second query server that is configured with

--no-evaluate-as-overlay --cache-at-frontier --warm-cache-only

and several commands:

• CodeQL: Warm Overlay-Base Cache for Query,
• CodeQL: Warm Overlay-Base Cache for Queries in Selected Files,
• CodeQL: Warm Overlay-Base Cache for Query Suite.

These commands are based on

• CodeQL: Run Query on Selected Database,
• CodeQL: Run Queries in Selected Files,
• CodeQL: Run Selected Query Suite,

but they run on the second query server and their results are not loaded into the "CodeQL Query Results" view.

One complication of this approach with two query servers is that only one of them can register the database at any given time. This is handled via withDatabaseInQsForWarmingOverlayBaseCache and seems to work well in practice. It does mean that running a query while a cache warming is ongoing will result in an error message. That seems better than silently running on the wrong kind of query server, though, which would be the effect on an alternative implementation with a single query server that gets killed and restarted.

[Copilot]

Pull Request Overview

This PR adds functionality to warm the overlay-base cache by introducing a second query server configured with specific cache-warming flags. The implementation adds new commands for cache warming operations and manages database registration between the two query servers.

Key changes:

• Adds a second query server instance dedicated to cache warming with flags --no-evaluate-as-overlay, --cache-at-frontier, and --warm-cache-only
• Implements three new commands for warming overlay-base cache: for single queries, multiple queries, and query suites
• Introduces database registration switching logic to ensure only one query server can register a database at a time

Reviewed Changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
local-databases.test.ts	Adds test coverage for database registration switching between query servers
query-server-client.ts	Adds cache warming configuration flags and descriptive logging for the warming query server
local-query-run.ts	Conditionally skips showing results when warming cache
local-queries.ts	Implements cache warming commands and routes them to the appropriate query server
ast-cfg-commands.ts	Updates function call to include new warmOverlayBaseCache parameter
extension.ts	Initializes the second query server and wires up restart logic
database-manager.ts	Implements database registration switching between query servers
loggers.ts	Adds dedicated logger for the cache warming query server
commands.ts	Defines type signatures for new cache warming commands
package.json	Registers new commands in VS Code command palette and context menus

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[nickrolfe]

The overall approach makes sense, and adding a second query-server was less invasive than I feared, but I have a few suggestions.

[nickrolfe]

Looks great.