Initial commit: Thread-safe ordered map for Go

- Insertion order preservation with O(1) lookups
- Thread-safe with RWMutex
- Zero-value usable
- Generic support (Go 1.18+)
- Snapshot-based iteration (deadlock-free)
- 100% test coverage with race detection

Author: ndbroadbent

.github/workflows/test.yml

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+name: Test
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        go-version: ['1.21', '1.22', '1.23']
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Set up Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: ${{ matrix.go-version }}
+
+    - name: Download dependencies
+      run: go mod download
+
+    - name: Run tests
+      run: go test -v -race -coverprofile=coverage.out -covermode=atomic
+
+    - name: Check coverage
+      run: |
+        coverage=$(go tool cover -func=coverage.out | grep total | awk '{print $3}' | sed 's/%//')
+        echo "Coverage: $coverage%"
+        if (( $(echo "$coverage < 100" | bc -l) )); then
+          echo "Error: Coverage is below 100%"
+          exit 1
+        fi
+
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v4
+      with:
+        files: ./coverage.out
+        fail_ci_if_error: false
+
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Set up Go
+      uses: actions/setup-go@v5
+      with:
+        go-version: '1.23'
+
+    - name: Run golangci-lint
+      uses: golangci/golangci-lint-action@v4
+      with:
+        version: latest

.gitignore

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+# Binaries
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary
+*.test
+
+# Coverage
+coverage.out
+coverage.html
+
+# Dependency directories
+vendor/
+
+# Go workspace
+go.work
+go.work.sum
+
+# IDE
+.idea/
+.vscode/
+*.swp
+*.swo
+*~
+
+# OS
+.DS_Store
+Thumbs.db

.golangci.yml

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+linters:
+  enable-all: true
+  disable:
+    # Deprecated linters
+    - exhaustivestruct
+    - golint
+    - ifshort
+    - interfacer
+    - maligned
+    - scopelint
+    - nosnakecase
+    - structcheck
+    - varcheck
+    - deadcode
+
+    # Not needed for library
+    - gochecknoglobals
+    - gomnd
+    - mnd
+    - wrapcheck
+    - exhaustruct
+    - ireturn
+    - varnamelen
+
+linters-settings:
+  lll:
+    line-length: 120
+  funlen:
+    lines: 100
+    statements: 50
+  gocognit:
+    min-complexity: 15
+  cyclop:
+    max-complexity: 15
+
+issues:
+  exclude-rules:
+    # Allow long lines in tests
+    - path: _test\.go
+      linters:
+        - lll
+        - funlen
+        - gocognit
+        - cyclop
+
+run:
+  timeout: 5m
+  tests: true

LICENSE

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+MIT License
+
+Copyright (c) 2025 DocSpring, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.