[bug] GithubIDContributions API undercounts PRs due to using dup_actor_login instead of dup_user_login

[qerogram]

Description

The GithubIDContributions API returns incorrect PR counts for users whose PRs were merged by maintainers without further activity from the author.

Root Cause

In cmd/api/api.go:1263-1271, the PR count query uses dup_actor_login:

select count(distinct id) as prs
from gha_issues
where is_pull_request = true
  and lower(dup_actor_login) = $1

However, dup_actor_login represents the last event actor (e.g., the maintainer who merged), not the PR author. The correct column should be dup_user_login. The same issue exists for the issues count query at line 1253-1261.

Impact

PRs that are "cleanly" merged (approve → merge with no further comments from the author) are not counted for the original author. This affects all CNCF projects.

Reproduction

Query the API:

curl -X POST https://devstats.cncf.io/api/v1 \
  -H "Content-Type: application/json" \
  -d '{"api":"GithubIDContributions","payload":{"github_id":"qerogram"}}'

Response: {"contributions":19,"issues":0,"prs":5}

But I have 6 merged PRs in envoyproxy/envoy:
#42447, #40578, #40534, #39937, #39829, #39702

Verified via Grafana query on https://envoy.devstats.cncf.io/explore:
-- Returns 5 rows (missing #40534)

  select
    distinct id,
    number, 
    title
  from
    gha_issues
  where
    is_pull_request = true
    and lower(dup_actor_login) = 'qerogram'

-- Returns 6 rows (correct)

  select
    distinct id,
    number, 
    title
  from
    gha_issues
  where
    is_pull_request = true
    and lower(dup_user_login) = 'qerogram'

PR #40534 has dup_actor_login = 'mattklein123' (the maintainer who merged it) but dup_user_login = 'qerogram' (the actual author).

[lukaszgryglicki]

I will take a look after the migration, but ID Contributions means that it is supposed to count "contributions" not only just merges, meaning any "contribution" and eon PRs, issues and so on. If there is a documentation that says it count PRs authored by given user not PRs that given user contributed to, then (and only then) it should be changed.