initial: fdroidserver-ipfs image

Downstream of registry.gitlab.com/fdroid/docker-executable-fdroidserver:master,
patched for publishing F-Droid repos over IPFS:

  - install Debian ipfs-cid so fdroidserver populates ipfsCIDv1 on every
    package file (APKs, icons, screenshots), which fdroidclient with an
    IPFS-gateway mirror routes via CID natively
  - rehash.py wrapper that adds ipfsCIDv1 to entry["index"], renames the
    index to a content-addressed filename, and re-signs entry.jar after
    `fdroid update` — closes the cache-busting gap on the index file itself
  - entrypoint.sh chains rehash automatically after any `fdroid update`,
    so existing fdroid-via-docker wrappers need no changes

See SPEC.md for the rationale and Change 2's algorithm; README.md for
end-user usage.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.claude/settings.json

@@ -0,0 +1,16 @@
+{
+  "$schema": "https://json.schemastore.org/claude-code-settings.json",
+  "permissions": {
+    "allow": [
+      "WebFetch(domain:gitlab.com)",
+      "WebFetch(domain:f-droid.org)",
+      "Read(research/**)",
+      "Glob",
+      "Grep",
+      "Bash(git clone *)",
+      "Bash(git:*)",
+      "Bash(ls:*)",
+      "Bash(wc:*)"
+    ]
+  }
+}