v5.3.6

Chat2DB Community 5.3.6 adds import preview and mapping, flexible CSV settings, MySQL transaction inspection, and execution-history filters, while improving table browsing, database compatibility, and desktop reliability.

## Added (4)

* CSV and Excel imports now offer data preview and column mapping on Web and Desktop, with field skipping and validation for duplicate mappings and missing required columns by @Aias00 and @openai0229 in [PR #2652](https://github.com/OtterMind/Chat2DB/pull/2652) and [PR #2887](https://github.com/OtterMind/Chat2DB/pull/2887).
* CSV imports support encoding, delimiter, text qualifier, and escape settings, header and data row ranges, empty-value handling, and date, time, and decimal formats by @Aias00 in [PR #2653](https://github.com/OtterMind/Chat2DB/pull/2653).
* MySQL 5.7 and 8.0 users can inspect active InnoDB transactions, duration, SQL, lock waits, and blocking connections, then open a console to inspect a related connection; unavailable metadata and insufficient privileges are explained explicitly by @Aias00 in [PR #2636](https://github.com/OtterMind/Chat2DB/pull/2636).
* Execution history can now be filtered by datasource, database, and schema, with SQL keyword search by @HandSonic in [PR #2696](https://github.com/OtterMind/Chat2DB/pull/2696).

## Improved (5)

* Copying table structure or data now shows an editable target-name confirmation and preserves the entered name on failure. Copy and truncate operations also handle special table names without double quoting by @openai0229 in [PR #2880](https://github.com/OtterMind/Chat2DB/pull/2880).
* Large text and JSON/JSONB cells use compact previews with full values loaded on demand, reducing large result-page loading failures. JSON formatting and compression also preserve value-inspector actions and reset the view to the start by @openai0229 in [PR #2882](https://github.com/OtterMind/Chat2DB/pull/2882).
* Workspace sidebars resize more smoothly while editor bounds stay aligned, and tabs and enabled watermarks use the theme accent when no custom datasource color is set by @openai0229 in [PR #2870](https://github.com/OtterMind/Chat2DB/pull/2870).
* Database, schema, and result-filter lists support horizontal scrolling for long values, keep short lists aligned, and show scrollbars only when needed by @openai0229 in [PR #2878](https://github.com/OtterMind/Chat2DB/pull/2878) and [PR #2881](https://github.com/OtterMind/Chat2DB/pull/2881).
* Built-in JDBC drivers can be downloaded again even when drivers are already installed. Concurrent downloads publish complete files safely, and background downloads no longer prevent application exit by @openai0229 and @HandSonic in [PR #2883](https://github.com/OtterMind/Chat2DB/pull/2883) and [PR #2687](https://github.com/OtterMind/Chat2DB/pull/2687).

## Fixed (18)

* Invalid WHERE or ORDER BY expressions no longer remove the table's filter editors or its last successful result; correcting or clearing the expression allows browsing to recover by @openai0229 in [PR #2899](https://github.com/OtterMind/Chat2DB/pull/2899).
* Editing multiple result rows no longer inherits current-statement execution options that caused saves to fail on MySQL connections with multi-statement execution disabled by @openai0229 in [PR #2877](https://github.com/OtterMind/Chat2DB/pull/2877).
* Repeated datasource saves no longer create duplicate connections, failed moves preserve the displayed tree, and creating a datasource inside a group expands and locates the new connection by @openai0229 in [PR #2891](https://github.com/OtterMind/Chat2DB/pull/2891) and [PR #2901](https://github.com/OtterMind/Chat2DB/pull/2901).
* Tree refreshes preserve hidden-node settings during overlapping refresh and hide operations, and a failed refresh after a successful datasource save is no longer reported as a failed save by @HandSonic in [PR #2743](https://github.com/OtterMind/Chat2DB/pull/2743).
* JSON and SQL files uploaded in Community Web can be submitted for import correctly by @Aias00 in [PR #2652](https://github.com/OtterMind/Chat2DB/pull/2652).
* SQL Server pagination recognizes only top-level ORDER BY clauses, and index metadata and generated DDL preserve ASC/DESC sort direction by @HandSonic in [PR #2694](https://github.com/OtterMind/Chat2DB/pull/2694) and [PR #2686](https://github.com/OtterMind/Chat2DB/pull/2686).
* Kingbase table DDL export works with catalog variants that lack expected information-schema columns and preserves identity, generated-column, enum, and default-value definitions by @openai0229 in [PR #2879](https://github.com/OtterMind/Chat2DB/pull/2879).
* Switching ClickHouse databases handles spaces, Unicode, and special characters without corrupting the JDBC URL by @HandSonic in [PR #2692](https://github.com/OtterMind/Chat2DB/pull/2692).
* DB2 procedure, function, and view definitions and related DDL exports no longer fail because JDBC queries contain trailing statement terminators by @HandSonic in [PR #2738](https://github.com/OtterMind/Chat2DB/pull/2738).
* Changing a Redis key to no expiration now clears its previous TTL by @HandSonic in [PR #2689](https://github.com/OtterMind/Chat2DB/pull/2689).
* Switching database accounts quickly no longer displays grants returned for a previously selected account by @HandSonic in [PR #2691](https://github.com/OtterMind/Chat2DB/pull/2691).
* Duplicate desktop launches activate the existing window, and file or protocol requests are retained during concurrent startup and exit handling by @openai0229 in [PR #2875](https://github.com/OtterMind/Chat2DB/pull/2875).
* AI chat restores table and view suggestions on explicit @ input, supports keyboard and mouse selection, and ignores stale suggestion responses by @openai0229 in [PR #2888](https://github.com/OtterMind/Chat2DB/pull/2888).
* Long custom-model connection-test errors stay inside a scrollable dialog instead of overflowing the page by @haizhi03 in [PR #2873](https://github.com/OtterMind/Chat2DB/pull/2873).
* Dashboard refresh controls leave the loading state when a refresh fails by @HandSonic in [PR #2688](https://github.com/OtterMind/Chat2DB/pull/2688).
* Interrupted task deletions can resume cleanup on application startup without deleting a newer export that reuses the original filename by @HandSonic in [PR #2742](https://github.com/OtterMind/Chat2DB/pull/2742).
* SSH connection-error logs no longer include passwords, private-key passphrases, or key-file fields by @Aias00 in [PR #2471](https://github.com/OtterMind/Chat2DB/pull/2471).
* The connection-close API now requires POST /api/connection/close with a JSON request body instead of GET query parameters. API clients that call this endpoint must update their requests by @HandSonic in [PR #2679](https://github.com/OtterMind/Chat2DB/pull/2679).

**Full Changelog**: https://github.com/OtterMind/Chat2DB/compare/v5.3.5...v5.3.6