meetings: advertise recurring meetings (#54)

* meetings: move to meetings/guidelines.md

Separating a page advertising recurring meetings from the guidelines for said meetings.

* meetings: Create README with overview of all meetings

One place listing all of our community meetings including working groups and office hours.

* Sidebar: update meeting page links

* meetings: add RMC description and link

Author: cassidyjames

SUMMARY.md

@@ -8,7 +8,8 @@
 - [Software Development Practices](software-development-practices/README.md)
   - [Agents](software-development-practices/agents.md)
 - [Documentation Guidelines](documentation.md)
-- [Meeting Guidelines](meetings.md)
+- [Meetings](meetings/README.md)
+  - [Guidelines](meetings/guidelines.md)
 
 ---
 

meetings/README.md

@@ -0,0 +1,54 @@
+# Meetings
+
+The ROOST community hosts meetings for open source projects, including office hours and working groups.
+
+- For a calendar of all events, see the [ROOST Community calendar] ([iCal URL])
+- For information on organizing meetings, see the [Meeting Guidelines](./guidelines.md)
+
+## Working Groups
+
+Advance the open source project/development, make decisions, discuss a specific project or initiative.
+
+### Coop
+
+_Every [Tuesday 1530–1600 UTC](https://zonr.dev/2026-04-21T15%3A30%3A00%2B00%3A00) (weekly); we plan to reduce the cadence to bi-weekly/fortnightly after the v1 release._
+
+Discuss, problem solve, and plan development of [Coop](https://github.com/roostorg/coop), the open source review tool for online safety.
+
+- [Google Meet](https://meet.google.com/kri-xque-kvy)
+- [Agendas + notes](https://github.com/roostorg/coop/discussions/categories/working-group-meetings)
+
+### Osprey
+
+_Every other [Friday 1830–1930 UTC](https://zonr.dev/2026-04-17T18%3A30%3A00%2B00%3A00) (bi-weekly/fortnightly)._
+
+Discuss, problem solve, and plan development of [Osprey](https://github.com/roostorg/osprey), the open source investigation tool and automated rules engine for online safety.
+
+- [Google Meet](https://meet.google.com/fui-ehrx-fxx)
+- [Agendas + notes](https://github.com/roostorg/osprey/discussions/categories/working-group-meetings)
+
+## Office Hours
+
+Provide community face-to-face time, answer questions, support (potential) adopters.
+
+### Model Community (RMC)
+
+_Every other [Wednesday 1730–1800 UTC](https://zonr.dev/2026-04-29T16%3A30%3A00%2B00%3A00) (bi-weekly/fortnightly)._
+
+Public meetings for the [RMC](https://github.com/roostorg/model-community), an ecosystem of developers, practicioners, and model creators making open safety models accessible and beneficial to the safety community.
+
+- [Google Meet](https://meet.google.com/knq-djnt-bvs)
+- [Agendas + notes](https://github.com/roostorg/model-community/discussions/categories/office-hours)
+
+### Hasher-Matcher-Actioner (HMA)
+
+_Every other [Wednesday 1700–1800 UTC](https://zonr.dev/2026-04-22T17%3A00%3A00%2B00%3A00) (bi-weekly/fortnightly)._
+
+Check in with adopters and contributors of [HMA](https://github.com/facebook/ThreatExchange/tree/main/hasher-matcher-actioner), the copy-detection reference implementation from Meta.
+
+- [Google Meet](https://meet.google.com/tem-pkjk-ydp)
+- [Project board](https://github.com/orgs/roostorg/projects/3/views/1)
+- [Agendas + notes](https://docs.google.com/document/d/1mQRLWL8bQzHrVFpaQjd6tHHRNXwQjpE2rr8DHoUFbm0/edit)
+
+[ROOST Community calendar]: https://calendar.google.com/calendar/embed?src=c_2f68741c36f377105f86dd8835d9469c0949d3abc9f2adc408e92095977a20dd%40group.calendar.google.com
+[iCal URL]: https://calendar.google.com/calendar/ical/c_2f68741c36f377105f86dd8835d9469c0949d3abc9f2adc408e92095977a20dd%40group.calendar.google.com/public/basic.ics