feat: add lychee.toml and lycheecache support

Signed-off-by: Rui Chen <rui@chenrui.dev>

.github/workflows/link-checker.yml

@@ -7,5 +7,15 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
+
+      - name: Restore lychee cache
+        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        with:
+          path: .lycheecache
+          key: cache-lychee-${{ github.sha }}
+          restore-keys: cache-lychee-
+
       - name: Link Checker
         uses: lycheeverse/lychee-action@885c65f3dc543b57c898c8099f4e08c8afd178a2 # v2
+        with:
+          args: --config ./lychee.toml README.md

.gitignore

@@ -0,0 +1,2 @@
+# Lychee link checker cache
+.lycheecache

lychee.toml

@@ -0,0 +1,24 @@
+# Lychee link checker configuration
+
+# Maximum number of retries per link
+max_retries = 3
+
+# Wait time between retries (in seconds)
+retry_wait_time = 5
+
+# Maximum number of concurrent network requests
+max_concurrency = 10
+
+# Accept 429 status codes (rate limiting) as valid after retries
+# This prevents CI failures due to temporary rate limits
+accept = [200, 204, 206, 429]
+
+# Alternative: Exclude hashicorp.com if rate limiting persists
+# Uncomment the line below if you want to skip hashicorp.com checks entirely
+# exclude = ['https://www\.hashicorp\.com/.*']
+
+# Cache results to avoid repeated checks
+cache = true
+
+# Use a custom user agent to be more identifiable
+user_agent = "awesome-tf link checker (https://github.com/shuaibiyy/awesome-tf)"