fix(docker): materialize @anydrop/shared as real dir, not workspace symlink

pnpm's workspace symlink (server/node_modules/@anydrop/shared → ../../../shared)
works locally but breaks on the Gitea Actions runner. TSC resolves the symlink
but cannot read through it, yielding TS2307 on "@anydrop/shared".

Fix: after building shared, copy its package.json + dist into
{server,web}/node_modules/@anydrop/shared as a plain directory before running
the dependent build. Module resolution becomes filesystem-local, independent
of BuildKit layer semantics or storage driver symlink handling.

server/Dockerfile

@@ -12,7 +12,17 @@ RUN pnpm install --frozen-lockfile
 
 COPY shared/ shared/
 COPY server/ server/
-RUN pnpm --filter @anydrop/shared run build && pnpm --filter @anydrop/server run build
+
+# Build shared first, then materialize it as a real directory inside
+# server/node_modules so TS module resolution does not rely on pnpm's
+# workspace symlink (which has been observed to break across build layers
+# on some CI runners / storage drivers).
+RUN pnpm --filter @anydrop/shared run build \
+ && test -f shared/dist/index.d.ts \
+ && rm -rf server/node_modules/@anydrop/shared \
+ && mkdir -p server/node_modules/@anydrop/shared \
+ && cp -r shared/package.json shared/dist server/node_modules/@anydrop/shared/ \
+ && pnpm --filter @anydrop/server run build
 
 # Runtime stage
 FROM node:20-alpine

web/Dockerfile

@@ -14,7 +14,12 @@ RUN pnpm install --frozen-lockfile
 
 COPY shared/ shared/
 COPY web/ web/
-RUN pnpm --filter @anydrop/shared run build && pnpm --filter @anydrop/web exec vite build
+RUN pnpm --filter @anydrop/shared run build \
+ && test -f shared/dist/index.d.ts \
+ && rm -rf web/node_modules/@anydrop/shared \
+ && mkdir -p web/node_modules/@anydrop/shared \
+ && cp -r shared/package.json shared/dist web/node_modules/@anydrop/shared/ \
+ && pnpm --filter @anydrop/web exec vite build
 
 # Runtime stage
 FROM nginx:alpine