scripts: add oe-go-mod-fetcher for Go module VCS resolution

Add the oe-go-mod-fetcher.py tool and supporting files for resolving
Go module dependencies via git repositories instead of module proxies.

oe-go-mod-fetcher.py:
  - Parses go.mod and go.sum to identify required modules
  - Resolves module paths to git repositories (handles vanity URLs)
  - Maps module versions to git commits
  - Generates SRC_URI entries for bitbake fetcher
  - Creates go-mod-git.inc and go-mod-cache.inc files
  - Supports monorepo detection and nested module handling
  - Caches resolution results for performance

extract-discovered-modules.py:
  - Helper script to extract module information from discovery cache
  - Used by go-mod-discovery.bbclass during build

Also adds .gitignore to exclude runtime caches from version control.

Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/scripts/.gitignore b/scripts/.gitignore
new file mode 100644
index 00000000..57fdcfc0
--- /dev/null
+++ b/scripts/.gitignore
@@ -0,0 +1,15 @@
+# Runtime caches generated by oe-go-mod-fetcher.py
+data/module-cache.json
+data/vanity-url-cache.json
+data/ls-remote-cache.json
+data/verify-cache.json
+data/.verify/
+
+# Python bytecode
+__pycache__/
+*.pyc
+
+# Editor/IDE files
+*.swp
+*~
+.cache/