ui: QueryaTextField, one text input for every form (#1465) #1733

Part of #1465 (step 4b).

Problem

Text inputs are shadcn's TextField in 56 places (31 files), plus InputFeature.leading/trailing in 3; another 18 are material.TextField styled by hand. The kit has only QueryaSearchField. Most uses on dev (2026-10-18): connection forms and the SSH tunnel section (17), Redis editors (16), Mongo (8), extensions, settings.

So inputs differ in height, border, focus ring and padding between forms, and between a shadcn field and a Material one in the same dialog.

Change

• QueryaTextField in the kit: sizes from QueryaControlSize (sm / md / lg, the heights the buttons use), placeholder, leading / trailing slots (icon or button, replacing InputFeature), obscure with a reveal toggle, multiline, error text, disabled / read-only, colours from the theme tokens.
• Migrate the shadcn fields first, then the hand-styled Material ones; keep keys and controllers.
• Guard: no shadcn TextField / InputFeature in lib/.

Acceptance

• One field component; a field and a button in one row have the same height (the fix(ui): small alignment and size inconsistencies from the Oct 2026 review #1480 item about the path field and Browse…).
• Widget tests: sizes, obscure toggle, error, leading / trailing; existing form tests pass.