v0.3.19

fix(bridge): Save in Setări actually persists; local config always wins

Two root-causes of today's "am salvat, dar tot nu se aplică" loop:

1. Local config was not authoritative. The merge in ws_client.py let
   server-pushed values overwrite some keys. Swapped the logic: now
   every key the GUI can touch (serial_port, serial_baud, baud,
   operator, operator_password, protocol, encoding_offset, bcc_algo,
   bcc_coverage, cmd_width) is NEVER taken from the server — server
   push only fills keys the local config doesn't provide (effectively
   just cmd_codes).

2. Save button appeared to work but the new values never hit the file.
   config.json had been created by LocalSystem during --install, so
   the ProgramData inheritance gave regular user accounts only Read.
   The write failed silently. Now:
     - Atomic write via .tmp + os.replace
     - After write, reload and compare every user-edited field; any
       mismatch surfaces a RED message with actionable fix ("run bridge
       as administrator, or icacls /grant Users:(M)")
     - config.py's save() + the GUI save both grant BUILTIN\Users
       Modify on the file immediately after writing, so the NEXT save
       from a regular user account always succeeds without admin

Companion: Setări dialog geometry bumped to 480×540 (Save button was
off-screen after v0.3.17 added the Protocol dialect dropdown).

Unit tests still pass (13/13).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>