[do not merge] dry-run of cutover

[matt-codecov]

depends on:

• tweak absorb repo script to handle subdirs that already exist #29
• use unified requirements image which is local-shared-friendly #30

also hacks the absorb script to include these PRs for worker/api:

• allow Makefile vars including REQUIREMENTS_TAG to be overridden codecov-api#1273
• allow Makefile vars including REQUIREMENTS_TAG to be overridden worker#1205

commands:

$ git checkout -b matt/absorb-dry-run-clean

$ ./tools/absorb-repo/absorb-repo.sh shared git@github.com:codecov/shared.git libs/shared

$ ./tools/absorb-repo/absorb-repo.sh worker git@github.com:codecov/worker.git apps/worker
$ cd apps/worker
$ sed -i '' 's/shared = { git.*/shared = { path = "..\/..\/libs\/shared" }/' pyproject.toml
$ uv sync
$ cd -
$ git add .
$ git commit -m 'use local shared for worker'

$ ./tools/absorb-repo/absorb-repo.sh codecov-api git@github.com:codecov/codecov-api.git apps/codecov-api
$ cd apps/codecov-api
$ sed -i '' 's/shared = { git.*/shared = { path = "..\/..\/libs\/shared" }/' pyproject.toml
$ uv sync
$ cd -
$ git add .
$ git commit -m 'use local shared for api'

local validation:

$ make devenv

$ make devenv.test.worker

$ make devenv.test.api

$ make devenv.test.shared

note that you need the umbrella conf file from our 1PW vault for all tests to pass locally.