fix: align toolchain versions and remove disabled/duplicate CI files (#32)

* fix: align toolchain versions and remove disabled/duplicate CI files

- mise.toml: bumped go 1.26.1 -> 1.26.4 to match go.mod/CI.
- CI: aligned golangci-lint version between ci.yml and mise.toml; pinned gofumpt v0.10.0 (was @latest).
- Removed two permanently-disabled workflow stubs (license-check.yml -> non-existent shared workflow; lint.yml -> redundant with ci.yml).
- Removed duplicate .github/CODEOWNERS (kept the richer root CODEOWNERS).

Verified: go build/vet/test pass; gofumpt clean; golangci-lint 0 issues.

* fix: restore code owners

* fix: remove duplicate .github/CODEOWNERS so root CODEOWNERS governs

The .github/CODEOWNERS (`* @GrayCodeAI/cli-maintainers`) took GitHub
precedence over the richer root CODEOWNERS, shadowing the per-directory
ownership (security-team for /redact/, devops-team for CI/build, etc.).
Removing it restores the intended ownership policy.

Author: Patel230

.github/CODEOWNERS

@@ -49,7 +49,7 @@ jobs:
           cache: true
       - name: gofumpt diff
         run: |
-          go install mvdan.cc/gofumpt@latest
+          go install mvdan.cc/gofumpt@v0.10.0
           out=$(gofumpt -l .)
           if [ -n "$out" ]; then
             echo "::error::gofumpt would reformat the following files:"
@@ -73,7 +73,7 @@ jobs:
           cache: true
       - uses: golangci/golangci-lint-action@v7
         with:
-          version: v2.1.0
+          version: v2.11.3
           install-mode: goinstall
           verify: false
           args: --timeout=5m

.github/workflows/ci.yml

@@ -1,6 +1,6 @@
 [tools]
 # Please also keep the version aligned in the go.mod file
-go = { version = '1.26.1', postinstall = "go install github.com/go-delve/delve/cmd/dlv@latest && go install gotest.tools/gotestsum@latest" }
+go = { version = '1.26.4', postinstall = "go install github.com/go-delve/delve/cmd/dlv@latest && go install gotest.tools/gotestsum@latest" }
 golangci-lint = '2.11.3'
 shellcheck = 'latest'
 tmux = 'latest'