docs: add README, per-resource examples, unit tests, CI, and pre-commit

- Add README.md with provider docs, resource/data-source reference, and
  development instructions
- Reorganize examples into per-resource-type subdirectories following
  Terraform provider conventions, add missing pypi/npm/puppet examples
- Add unit tests for helpers, HTTP client, model conversions, and
  provider registration
- Add Woodpecker CI pipelines for lint, test, and build
- Add pre-commit config with standard and Go-specific hooks

.woodpecker/build.yml

@@ -0,0 +1,8 @@
+when:
+  - event: [push, pull_request]
+
+steps:
+  - name: build
+    image: golang:1.25
+    commands:
+      - make build

.woodpecker/test.yml

@@ -0,0 +1,13 @@
+when:
+  - event: [push, pull_request]
+
+steps:
+  - name: lint
+    image: golang:1.25
+    commands:
+      - make lint
+
+  - name: test
+    image: golang:1.25
+    commands:
+      - make test