Add CI release workflow, CHANGELOG.md, issue templates

- .github/workflows/release.yml: on tag push, build exe via ps2exe,
  package portable zip, attach SHA-256, create GitHub Release.
- CHANGELOG.md: Keep a Changelog format, semver.
- .github/ISSUE_TEMPLATE/: bug_report.yml + feature_request.yml + config.yml
  routing security reports to private advisories.

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,55 @@
+name: Bug report
+description: Something doesn't work as expected
+labels: ["bug"]
+body:
+  - type: input
+    id: version
+    attributes:
+      label: Version
+      description: Visible in the startup banner.
+      placeholder: v1.0.0
+    validations:
+      required: true
+
+  - type: textarea
+    id: steps
+    attributes:
+      label: Steps to reproduce
+      placeholder: |
+        1. ...
+        2. ...
+        3. ...
+    validations:
+      required: true
+
+  - type: textarea
+    id: expected
+    attributes:
+      label: What you expected to happen
+    validations:
+      required: true
+
+  - type: textarea
+    id: actual
+    attributes:
+      label: What actually happened
+      description: Paste any error output verbatim. Screenshots are welcome.
+    validations:
+      required: true
+
+  - type: input
+    id: os
+    attributes:
+      label: Windows version
+      placeholder: e.g. Windows 11 24H2
+
+  - type: input
+    id: adapter
+    attributes:
+      label: Adapter (if relevant)
+      placeholder: e.g. Realtek USB GbE Family Controller
+
+  - type: textarea
+    id: extra
+    attributes:
+      label: Anything else?

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Security vulnerability
+    url: https://github.com/Engelgardt23/netswitch/security/advisories/new
+    about: Please report security issues privately via GitHub Security Advisories — not as a public issue.

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,23 @@
+name: Feature request
+description: Suggest a new feature or an improvement
+labels: ["enhancement"]
+body:
+  - type: textarea
+    id: motivation
+    attributes:
+      label: What's the use case?
+      description: What are you trying to do, and why is the current behavior not enough?
+    validations:
+      required: true
+
+  - type: textarea
+    id: proposal
+    attributes:
+      label: Proposed solution
+    validations:
+      required: true
+
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: Alternatives considered

.github/workflows/release.yml

@@ -0,0 +1,77 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*.*.*'
+
+permissions:
+  contents: write
+
+jobs:
+  build:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Resolve version from tag
+        id: ver
+        shell: bash
+        run: echo "version=${GITHUB_REF_NAME#v}" >> "$GITHUB_OUTPUT"
+
+      - name: Install ps2exe
+        shell: pwsh
+        run: Install-Module -Name ps2exe -Scope CurrentUser -Force -AllowClobber
+
+      - name: Build executable
+        shell: pwsh
+        run: |
+          Import-Module ps2exe
+          $ver = '${{ steps.ver.outputs.version }}'
+          Invoke-ps2exe -inputFile netswitch.ps1 -outputFile netswitch.exe `
+              -title "netswitch" -description "NIC IP/DHCP toggle - made by engelgardt" `
+              -company "engelgardt" -version "$ver.0" `
+              -requireAdmin
+
+      - name: Package portable folder
+        shell: pwsh
+        run: |
+          $ver = '${{ steps.ver.outputs.version }}'
+          $folder = "netswitch-v$ver"
+          New-Item -ItemType Directory -Path $folder | Out-Null
+          Copy-Item netswitch.exe $folder/
+          @"
+          netswitch v$ver - portable edition
+          made by engelgardt
+
+          Quickly set a Windows network adapter to a static IP or back to DHCP.
+
+          USAGE
+            Double-click netswitch.exe.
+            Accept the UAC prompt.
+            Pick the NIC, then choose mode (Static / DHCP).
+            Press Enter to exit.
+
+          NOTES
+            - Nothing is installed. Delete the folder to remove.
+            - Requires Windows 10/11.
+            - PowerShell is bundled into the exe via ps2exe; nothing extra needed.
+          "@ | Out-File -FilePath "$folder/README.txt" -Encoding UTF8
+          Compress-Archive -Path $folder -DestinationPath "netswitch-portable-v$ver.zip"
+
+      - name: Generate SHA-256 checksum
+        shell: pwsh
+        run: |
+          $ver = '${{ steps.ver.outputs.version }}'
+          $zip = "netswitch-portable-v$ver.zip"
+          $hash = (Get-FileHash -Algorithm SHA256 $zip).Hash.ToLower()
+          "$hash  $zip" | Out-File -FilePath "$zip.sha256" -Encoding ASCII -NoNewline
+          Get-Content "$zip.sha256"
+
+      - name: Create release
+        uses: softprops/action-gh-release@v2
+        with:
+          files: |
+            netswitch-portable-v${{ steps.ver.outputs.version }}.zip
+            netswitch-portable-v${{ steps.ver.outputs.version }}.zip.sha256
+          generate_release_notes: true

CHANGELOG.md

@@ -0,0 +1,21 @@
+# Changelog
+
+All notable changes to **netswitch** are documented in this file.
+
+The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and the project uses [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [1.0.0] - 2026-05-16
+### Added
+- First public release on GitHub.
+- Portable `.exe` (~30 KB) built from PowerShell via ps2exe.
+- Self-elevation through UAC.
+- Physical wired NIC filter — Wi-Fi, VPN, virtual, Hyper-V, VMware, VirtualBox, TAP/TUN, WireGuard, OpenVPN, Tailscale, ZeroTier, Bluetooth, Loopback and WAN Miniport adapters are hidden from the picker.
+- Two modes: **Static** (default `10.10.10.1/24`, optional gateway) and **DHCP**.
+- Current IPv4 configuration is printed after the change.
+- Auto-update check on startup: polls GitHub `/releases/latest` with a 3-second timeout and offers to open the download page if a newer version exists. Silent on offline / API errors.
+- MIT licensed.
+
+[Unreleased]: https://github.com/Engelgardt23/netswitch/compare/v1.0.0...HEAD
+[1.0.0]: https://github.com/Engelgardt23/netswitch/releases/tag/v1.0.0