cli: --recreate alias, exec --env, --log-level filter

[bilby91]

Batches three small CLI follow-ups since they all touch cmd/devcontainer/.

Closes #74, closes #75, closes #76.

#76 — `up --recreate` alias

Same bool as `--remove-existing-container`, two flag names. Keeps muscle memory from upstream `@devcontainers/cli` while exposing the library's own naming.

#75 — `exec -e/--env KEY=VALUE`

Repeatable. Split on the first `=` so values containing `=` (URLs, base64) survive. Entries without `=` are rejected:
```
$ devcontainer exec -e MALFORMED -- echo ok
error: invalid --env "MALFORMED": expected KEY=VALUE
```

#74 — `--log-level` filter

Previously parsed but never applied. Now gates the two chatty event types:

• `events.BuildLogEvent` (raw docker build output)
• `events.LifecycleOutputEvent` (raw lifecycle stdout/stderr)

behind `debug`. Progress, warnings, and container state changes still render at `info`. Unknown values rejected at command entry. `trace` is reserved (currently identical to `debug`) so the flag's contract doesn't break once there are more granular event types to gate.

Test plan

• `up --recreate` brings up workspace (smoke)
• `exec -e FOO=hello -e BAR=world -- sh -c 'echo $FOO $BAR'` prints `hello world`
• `exec -e MALFORMED -- echo ok` exits 1 with the expected message
• `run-user-commands` at default level shows only the ✓ summary (no lifecycle stdout flood)
• `up --log-level loud` exits 1 with the expected message
• `go vet`, `golangci-lint run`, linux cross-build clean

🤖 Generated with Claude Code

Summary by CodeRabbit

Release Notes

• New Features
  • Added --log-level flag to control output verbosity (info, debug, trace levels).
  • Added repeatable --env/-e flags to the exec command for setting environment variables.
  • Added --recreate flag as an alias for --remove-existing-container.
  • Event output now respects configured log levels.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 5aff9373-c13b-4d86-89d6-30e3a22daccd

📥 Commits

Reviewing files that changed from the base of the PR and between 47b6958 and 41f955d.

📒 Files selected for processing (5)

• cmd/devcontainer/down.go
• cmd/devcontainer/events.go
• cmd/devcontainer/exec.go
• cmd/devcontainer/root.go
• cmd/devcontainer/up.go

---

📝 Walkthrough

Walkthrough

The PR implements log-level-gated event printing, adds environment variable support to the exec command, and introduces a --recreate flag alias for up. Changes span five files across event handling, command configuration, and CLI parsing.

Changes

CLI Features and Event Verbosity

Layer / File(s)	Summary
Log level type and root-level parsing cmd/devcontainer/events.go, cmd/devcontainer/root.go	Defines logLevel type and levelInfo/levelDebug/levelTrace constants. The rootFlags.level() helper parses --log-level from CLI input and returns the corresponding logLevel or rejects unsupported values.
Event printer verbosity control cmd/devcontainer/events.go	startEventPrinter now accepts a logLevel and passes it to printEvent. printEvent gates lifecycle line output and build log lines behind debug-level threshold, suppressing them at info level while printing other event types unconditionally.
Log level integration in up and down commands cmd/devcontainer/up.go, cmd/devcontainer/down.go	Both commands now call rf.level() to resolve the log level early and pass it to startEventPrinter instead of using the no-argument initialization path.
Environment variable support in exec command cmd/devcontainer/exec.go	The exec command adds a repeatable --env/-e flag that collects KEY=VALUE pairs, parses them into a map preserving values with embedded =, rejects entries without =, and wires them to ExecOptions.Env.
--recreate flag alias in up command cmd/devcontainer/up.go	The up command registers --recreate as a boolean flag alias for the existing --remove-existing-container behavior.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Possibly related PRs

• crunchloop/devcontainer#79: Extends the same Cobra CLI scaffold by wiring log-level filtering into events, adding environment variable parsing to exec, and defining log-level validation at the root level.

Poem

🐰 With log-level whispers and env vars to keep,
The CLI grows sharper, digging deeper and deep.
Recreate shorthand, events that obey—
Three features refined in one hopping relay! 🌿

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 55.56% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title concisely and accurately summarizes all three main changes: --recreate alias, exec --env flag, and --log-level filtering.
Linked Issues check	✅ Passed	All three linked issues (#74, #75, #76) are fully addressed: log-level filtering gates verbose events to debug+, exec gains repeatable --env/-e flag with proper parsing, and --recreate alias is added for --remove-existing-container.
Out of Scope Changes check	✅ Passed	All changes are directly scoped to the three linked issues; no unrelated modifications detected in the changeset.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch cli/batch-74-76

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