feat: beautified JSON display in Details sidebar with syntax highlighting

[datlechin]

Summary

• Auto-pretty-print and syntax-highlight JSON values in the Cell Inspector (Details sidebar) — both read-only and editable modes
• Content-based JSON detection for TEXT/LONGTEXT/VARCHAR columns storing JSON (not just native JSON/JSONB column types)
• Extract JSONSyntaxTextView into a reusable component shared between the JSON editor popover and the sidebar
• Double-clicking a text cell containing JSON now opens the JSON editor popover (same as native JSON columns)

Details

Sidebar rendering (before → after):

Mode	Before	After
Read-only	Raw compact string in plain Text	Auto-pretty-printed + syntax highlighted (blue keys, red strings, purple numbers, orange booleans/null)
Editable	Plain TextField, manual "Pretty Print" button	Auto-pretty-printed + syntax highlighted editor, compacts on save
Menu actions	"Pretty Print" (manual)	"Compact" + "Copy Formatted"
Context menu	"Copy Value" only	"Copy Value" + "Copy Formatted"

Content-based JSON detection:

• New String.looksLikeJson property: only parses values starting with { or [ to avoid false positives with bare primitives
• Applied in: sidebar (both modes), data grid double-click, inline edit blocking

Test plan

• Open a table with a native JSON/JSONB column → verify sidebar shows pretty-printed, syntax-highlighted JSON
• Open a table with a TEXT/LONGTEXT column containing JSON → verify same beautified display
• Edit a JSON value in the sidebar → verify it compacts on save
• Double-click a TEXT cell containing JSON → verify JSON editor popover opens
• Verify non-JSON text values in TEXT columns are unaffected (plain text editor)
• Test with large JSON (>10K chars) → verify highlighting caps at 10K
• Test "Copy Formatted" and "Compact" menu actions
• Verify read-only connections show beautified JSON without edit capability