Function name histogram #17

Why

The functions teams write and call (transfer, mint, initialize, deposit) show what the ecosystem is actually building.

In this repo today

indexer/wasm.py reads only the contract metadata section, and invokes are not indexed. Both halves need new parsing.

What to build

• Declared functions: read the function names from each uploaded wasm's contractspecv0 custom section (extend indexer/wasm.py).
• Called functions: record the function name of each invoke_host_function call in the parser, as part of the Invoke event described in the resource fee issue.
• Tables in db.py for each, and an API route returning the top 30 names plus "other", separately for declared and called.
• A DistributionBar on the home page showing both.

Acceptance criteria

• Counts from the spec and from invocations are kept separate.
• A fixture wasm with known functions parses to exactly those names.

See CONTRIBUTING.md for conventions.