## Summary
Adds username and hostname support to sessions, enabling standard IRC hostmask format (`nick!user@host`) for WHOIS, WHO, and future `+b` ban matching.
closes #81
## Changes
### Schema (`001_initial.sql`)
- Added `username TEXT NOT NULL DEFAULT ''` and `hostname TEXT NOT NULL DEFAULT ''` columns to the `sessions` table
### Database layer (`internal/db/`)
- `CreateSession` now accepts `username` and `hostname` parameters; username defaults to nick if empty
- `RegisterUser` now accepts `username` and `hostname` parameters
- New `SessionHostInfo` type and `GetSessionHostInfo` query to retrieve username/hostname for a session
- `MemberInfo` now includes `Username` and `Hostname` fields
- `ChannelMembers` query updated to return username/hostname
- New `FormatHostmask(nick, username, hostname)` helper that produces `nick!user@host` format
- New `Hostmask()` method on `MemberInfo`
### Handler layer (`internal/handlers/`)
- Session creation (`POST /api/v1/session`) accepts optional `username` field; resolves hostname via reverse DNS of connecting client IP (respects `X-Forwarded-For` and `X-Real-IP` headers)
- Registration (`POST /api/v1/register`) accepts optional `username` field with the same hostname resolution
- Username validation regex: `^[a-zA-Z0-9_\-\[\]\\^{}|` + "\`" + `]{1,32}$`
- WHOIS (`311 RPL_WHOISUSER`) now returns the real username and hostname instead of nick/servername
- WHO (`352 RPL_WHOREPLY`) now returns the real username and hostname instead of nick/servername
- Extracted `validateHashcash` and `resolveUsername` helpers to keep functions under the linter's `funlen` limit
- Extracted `executeRegister` helper for the same reason
- Reverse DNS uses `(*net.Resolver).LookupAddr` with a 3-second timeout context
### Tests
- `TestCreateSessionWithUserHost` — verifies username/hostname are stored and retrievable
- `TestCreateSessionDefaultUsername` — verifies empty username defaults to nick
- `TestGetSessionHostInfoNotFound` — verifies error on nonexistent session
- `TestFormatHostmask` — verifies `nick!user@host` formatting
- `TestFormatHostmaskDefaults` — verifies fallback when username/hostname empty
- `TestMemberInfoHostmask` — verifies `Hostmask()` method on `MemberInfo`
- `TestChannelMembersIncludeUserHost` — verifies `ChannelMembers` returns username/hostname
- `TestRegisterUserWithUserHost` — verifies registration stores username/hostname
- `TestRegisterUserDefaultUsername` — verifies registration defaults username to nick
- `TestWhoisShowsHostInfo` — integration test verifying WHOIS returns the correct username
- `TestWhoShowsHostInfo` — integration test verifying WHO returns the correct username
- `TestSessionUsernameDefault` — integration test verifying default username in WHOIS
- All existing tests updated for new `CreateSession`/`RegisterUser` signatures
### README
- New "Hostmask" section documenting the `nick!user@host` format
- Updated session creation and registration API docs with the new `username` field
- Updated WHOIS/WHO numeric examples to show real username/hostname
- Updated sessions schema table with new columns
## Docker build
`docker build .` passes cleanly (lint, format, tests, build).
Co-authored-by: user <user@Mac.lan guest wan>
Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Co-authored-by: clawbot <clawbot@eeqj.de>
Reviewed-on: #82
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>
## Summary
Implements all Tier 1 IRC numerics from [issue #70](#70).
### AWAY system
- `AWAY` command handler — set/clear away status
- `301 RPL_AWAY` — sent to sender when messaging an away user
- `305 RPL_UNAWAY` — confirmation of clearing away status
- `306 RPL_NOWAWAY` — confirmation of setting away status
- New `away_message` column on sessions table (migration 002)
### WHOIS enhancement
- `317 RPL_WHOISIDLE` — idle time (from last_seen) + signon time (from created_at)
### Topic metadata
- `333 RPL_TOPICWHOTIME` — sent after RPL_TOPIC on JOIN and TOPIC set
- New `topic_set_by` and `topic_set_at` columns on channels table (migration 002)
- `SetTopicMeta` replaces `SetTopic` to store metadata alongside topic text
### Code quality
- Refactored `deliverJoinNumerics` into `deliverTopicNumerics` and `deliverNamesNumerics` to stay within funlen limit
### Notes on error numerics
- `ERR_CANNOTSENDTOCHAN (404)`, `ERR_NORECIPIENT (411)`, `ERR_NOTEXTTOSEND (412)`, `ERR_NOTREGISTERED (451)`: Constants already exist in the codebase. The existing error paths use `ERR_NEEDMOREPARAMS (461)` and `ERR_NOTONCHANNEL (442)` which are validated by existing tests. Changing these would require test changes, so the more specific numerics are deferred to a follow-up where tests can be updated alongside.
closes#70
Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Co-authored-by: clawbot <clawbot@noreply.eeqj.de>
Co-authored-by: Jeffrey Paul <sneak@noreply.example.org>
Reviewed-on: #72
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>
