Add a FixType filter to the Fix common errors rule list

[ivandrofly]

Stacked on #14442 (the FixType property on IFixCommonError); this PR's own change is the top commit.

Summary

• Add a "Type" combo to the step 1 toolbar of Fix common errors that filters the rule list by the rule's FixType (All, Time, Formatting, Dialog, Punctuation, Casing, Spacing, Characters, OCR).
• The type filter is combined with the "Search rules..." text box, which was created but never added to the window; both now sit in the step 1 toolbar and hide in step 2.
• FixRuleDisplayItem resolves its FixType once from the fix classes (one lazily built name-to-type map), so libse stays the single source of truth; the copy constructor carries it into profile clones.
• Filtering always reads the profile's full rule list, so hidden rules keep their selection and apply/save still see them. The active filter follows a profile switch.
• New language strings: FixTypeFormatting, FixTypeDialog, FixTypePunctuation, FixTypeOcr (the other four reuse existing General strings); English.json regenerated.
• Tests: FixCommonErrorsRuleFilterTests (type filter, AND with search, profile switch, hidden selection kept, type resolution for every default and language-specific rule, window wiring and step visibility).

Test plan

• Open a subtitle, Tools > Fix common errors: the search box and a "Type" combo appear in the top row of step 1 and are hidden in step 2
• Pick "Time": only the four timing rules remain; type "short" in the search box: two remain; pick "All": the full list is back
• With "Time" selected, click Select all / Invert selection: only the visible rows change
• Select a profile, choose a type, switch profile: the filter stays applied
• Filter to "Time", untick a rule, pick "All", then "Go to apply fixes": rules hidden by the filter still run according to their tick state
• dotnet test tests/UI/UITests.csproj: FixCommonErrorsRuleFilterTests pass

🤖 Generated with Claude Code

https://claude.ai/code/session_01SXEWrgv5uAnSzDgxFupSHZ

[niksedk]

Hi @ivandrofly, closing this along with #14442 - see my note there. I'd rather keep the Fix common errors rule list simple for now, so I'm not going to add a type filter at this point. The observation that the "Search rules..." box was never added to the window is a good catch though, so I'll look at that separately.

Thanks for the work on it!