fix(dot-repeat): don't replay non-editing Ex commands

[coxxny]

What this PR does / why we need it:

Aligns dot-repeat behavior with Vim semantics: . should only repeat the last editing (buffer-changing) action and must not replay Ex commands.
Currently, . can replay Ex commands (e.g., :bn, :b<number>, :ls, :pwd), which causes unintended navigation and breaks common “edit → .” workflows. This PR consolidates the rule so that all Ex commands are excluded from dot-repeat.

Scope & notes

• This is a spec change; a freeze that occurred when pressing . after executing Ex commands discovered during validation is tracked and fixed separately in [Bug] Pressing . twice after an Ex command with no prior edit state causes a freeze #9809.

Which issue(s) this PR fixes

Fixes #9807

Special notes for your reviewer:

Build & Test evidence

Build log (yarn build)

yarn run v1.22.22
$ gulp build
(node:155189) [DEP0060] DeprecationWarning: The `util._extend` API is deprecated. Please use Object.assign() instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
[16:10:30] Using gulpfile ~/document/repositories/Vim/gulpfile.js
[16:10:30] Starting 'build'...
[16:10:30] Starting 'webpack'...
[16:10:47] asset extension.js 956 KiB [emitted] [minimized] (name: main) 1 related asset
orphan modules 73.5 KiB [orphan] 15 modules
runtime modules 793 bytes 4 modules
cacheable modules 2.63 MiB
  modules by path ./src/ 1.39 MiB 162 modules
  modules by path ./node_modules/ 1.19 MiB 137 modules
  modules by path ./*.ts 27 KiB
    ./extension.ts 3.63 KiB [built] [code generated]
    ./extensionBase.ts 23.4 KiB [built] [code generated]
  ./package.json 32.7 KiB [built] [code generated]
+ 17 modules
webpack 5.102.0 compiled successfully in 15676 ms

asset extensionWeb.js 2.17 MiB [emitted] [minimized] (name: main) 1 related asset
runtime modules 344 bytes 2 modules
modules by path ./src/ 1.34 MiB 155 modules
modules by path ./node_modules/ 663 KiB
  ./node_modules/process/browser.js 5.29 KiB [built] [code generated]
  ./node_modules/parsimmon/build/parsimmon.umd.min.js 14.9 KiB [built] [code generated]
  ./node_modules/path-browserify/index.js 15.8 KiB [built] [code generated]
  ./node_modules/lodash/lodash.js 531 KiB [built] [code generated]
  ./node_modules/queue/index.js 4.03 KiB [built] [code generated]
  ./node_modules/untildify/index.js 331 bytes [built] [code generated]
  + 4 modules
modules by path ./*.ts 24 KiB
  ./extensionWeb.ts 682 bytes [built] [code generated]
  ./extensionBase.ts 23.4 KiB [built] [code generated]
external "vscode" 42 bytes [built] [code generated]
./package.json 32.7 KiB [built] [code generated]
webpack 5.102.0 compiled successfully in 8207 ms
[16:10:47] Finished 'webpack' after 17 s
[16:10:47] Starting 'commit-hash'...
[16:10:47] Finished 'commit-hash' after 12 ms
[16:10:47] Finished 'build' after 17 s
Done in 18.86s.

Test log (tail of npx gulp test)

    ✔ s+[num]
    ✔ s-[num]
    ✔ b
    ✔ b+
    ✔ b-
    ✔ b[num]
    ✔ b+[num]
    ✔ b-[num]
  3088 passing (2m)
  10 pending
[main 2025-11-01T07:17:40.401Z] Extension host with pid 220 exited with code: 0, signal: unknown.
Exit code:   0

behavior after this change

example1.txt.-.test.-.Visual.Studio.Code.2025-11-01.16-32-42.mp4

[coxxny]

@J-Fields
This change may increase the occurrence of the freezes mentioned in PR #9809, so please merge it before this PR.
The problem is fixed in that PR.