One wrong-typed field in a single profiles.json/commands.json entry discards every stored entry, and the next save erases them #168

What's wrong

#125 and #133 made loading tolerate one bad entry: ToProfile (Keybinding/Services/JsonKeybindingRepository.cs:126-160) and ToCommand (228-244) skip an entry whose values fail validation (ArgumentException). But that per-entry handling only runs after the whole file has deserialized successfully:

• LoadAllProfilesInternalAsync (JsonKeybindingRepository.cs:98-119) calls JsonSerializer.Deserialize<List<ProfileDto>> on the whole file and catches JsonException by returning [].
• LoadCommandsAsync (199-221) does the same for commands.json.

A JSON type mismatch inside any one element ("name": 5, "notes": "CTRL" instead of an array, "notes": [5], "category": 5) makes System.Text.Json throw JsonException for the whole list, so every entry is dropped, not just the bad one. SaveProfileAsync (43-72) then reads the file back the same way, gets [], and writes only what's in memory.

Failure scenario (reproduced with a scratch MSTest)

1. Save profiles a (with file.save bound to Ctrl+S) and b.
2. Hand-edit profiles.json so only profile b has "name": 5.
3. New KeybindingManager → InitializeAsync() → GetAllProfiles().Count == 0; valid profile a is gone too.
4. CreateProfile("c") + SaveAsync() → profiles.json now contains only c. Profile a and its binding are permanently lost.

This differs from #157 (torn/syntactically corrupt file) and #148 (concurrent saves): here the file is valid JSON with one off-schema element, the case #125/#133 meant to make survivable. The #157 fix (atomic writes, moving a corrupt file aside) would prevent the permanent loss but still load zero profiles.

Suggested fix

• Deserialize to List<JsonElement> (or JsonArray), then per element call element.Deserialize<ProfileDto>(_jsonOptions) / <CommandDto> inside a try that catches both JsonException and ArgumentException, skipping only that entry. Apply the same per-ChordDto within a profile.
• Keep the whole-file catch only for a file that doesn't parse at all.
• Regression tests: one entry with "name": 5 in profiles.json still loads the other profiles; same for a wrong-typed field in commands.json.