[REF] use single main branch with per-version config directories

Replace per-branch versioning (16.0, 18.0...) with a single main branch
containing version-specific subdirectories under config/.

Structure:
- config/common/: shared files deployed to all versions
- config/16.0/: Odoo 16.0 specific configs (pylintrc, ruff, pre-commit)

The deploy workflow now:
- Triggers on push to main
- Auto-detects available versions from config/*/
- For each target repo, deploys common + version-specific files

Also enables Gitea native cache in pre-commit workflow.

config/16.0/.ruff.toml

@@ -0,0 +1,31 @@
+
+target-version = "py310"
+fix = true
+
+[lint]
+extend-select = [
+    "B",
+    "C90",
+    "E501",  # line too long (default 88)
+    "I",  # isort
+    "UP",  # pyupgrade
+]
+extend-safe-fixes = ["UP008"]
+exclude = ["setup/*"]
+
+[format]
+exclude = ["setup/*"]
+
+[lint.per-file-ignores]
+"__init__.py" = ["F401", "I001"]  # ignore unused and unsorted imports in __init__.py
+"__manifest__.py" = ["B018"]  # useless expression
+
+[lint.isort]
+section-order = ["future", "standard-library", "third-party", "odoo", "odoo-addons", "first-party", "local-folder"]
+
+[lint.isort.sections]
+"odoo" = ["odoo"]
+"odoo-addons" = ["odoo.addons"]
+
+[lint.mccabe]
+max-complexity = 16