fix(dotAI): EmbeddingContentListener runs CREATE EXTENSION vector on archive/delete even when dotAI is disabled

Problem Statement

When dotAI is not configured/disabled, the embeddings content listener still attempts to initialize the PostgreSQL vector extension on archive/unpublish/delete operations. On a standard PostgreSQL instance without pgvector, this throws:

org.postgresql.util.PSQLException: ERROR: extension "vector" is not available
  Detail: Could not open extension control file ".../vector.control": No such file or directory.
  Hint: The extension must first be installed on the system where PostgreSQL is running.

The connection is then marked broken (SQLSTATE 0A000). The operation itself (archive/unpublish/delete) still completes — only the embeddings cleanup fails — but it logs a stack trace intermittently and forces a pgvector requirement on customers who don't use AI at all.

Root cause (confirmed with @ivan.hoffmann):

• EmbeddingsInitializer.init() subscribes EmbeddingContentListener unconditionally at startup — no AI-enabled gate, and no toggle to disable just this listener.
• EmbeddingContentListener.deleteFromIndexes()'s only guard is a call to getConfigJson(host). But getConfigJson() wraps getAppConfig() in Try.of(...).getOrElse(new JSONObject()), so when dotAI is disabled the DotAIAppConfigDisabledException is swallowed and converted to an empty {}. deleteFromIndexes() does not check for the empty config and proceeds to call EmbeddingsAPIImpl.deleteEmbedding() regardless.
• deleteEmbedding() triggers the lazy EmbeddingsFactory.impl singleton, whose constructor runs initVectorExtension() → CREATE EXTENSION vector.
• The publish/add path (addToIndexesIfNeeded) gets the same empty config but iterates over zero indexes → harmless no-op. Only the delete path fires the error, which is why it appears intermittently (archive/unpublish/delete only).

Steps to Reproduce

1. Use a standard PostgreSQL DB without the pgvector extension installed.
2. Leave dotAI unconfigured (no API key/URLs in Settings → Apps → dotAI).
3. Archive, unpublish, or delete any contentlet.
4. Observed: EmbeddingContentListener.onArchive → deleteFromIndexes → EmbeddingsAPIImpl.deleteEmbedding → EmbeddingsFactory.<init> → initVectorExtension → CREATE EXTENSION vector throws PSQLException: extension "vector" is not available; the pooled connection is marked broken.

Expected vs. Actual

• Expected: With dotAI disabled, no embeddings/vector initialization runs. No pgvector requirement on the database.
• Actual: The delete path attempts CREATE EXTENSION vector and errors on standard Postgres.

Acceptance Criteria

• With dotAI disabled, archive/unpublish/delete does not attempt to initialize the vector extension or touch the embeddings layer.
• No PSQLException: extension "vector" is not available is logged when dotAI is disabled.
• No pgvector extension is required for normal content operations when AI is not in use.
• Integration test covering archive/delete on a disabled-dotAI host.

Proposed Fix (per @ivan.hoffmann)

Either:

• Have deleteFromIndexes() check for an empty config JSON and return early, or
• Have getConfigJson() return an Optional instead of swallowing DotAIAppConfigDisabledException, and have callers short-circuit when absent.

Affected Version

25.07.10 LTS (present since the listener was registered in #28770 / 24.06.21). Please confirm whether a fix should be backported to the 25.07.x LTS line.

Proposed Priority

Priority 2 - Important

External Links

• Freshdesk ticket: https://dotcms.freshdesk.com/a/tickets/37875
• Slack confirmation: dotAI engineering thread in #feat-dotai (@ivan.hoffmann confirmed root cause and that no existing issue covers this)

Start with EmbeddingContentListener.deleteFromIndexes(), getConfigJson(), and EmbeddingsAPIImpl.deleteEmbedding(); trace how EmbeddingsFactory initializes the vector extension when dotAI is disabled. Run the relevant content archive, unpublish, or delete integration tests, then add coverage for a disabled-dotAI host and verify these operations do not touch embeddings or log a missing-vector error.