Add dental module phase 4 and phase 5 documentation, including treatment estimates, clinical operations, and preset content

- Introduced phase 4 documentation detailing treatment estimates, data models, state machines, API endpoints, and new dashboard metrics.
- Added phase 5 documentation covering consumables, lab operations, periodontal charts, sterilization cycles, clinical images, and a checklist for professional review.
- Created a preset content document outlining default dental service packages and protocols for clinics.

docs/adr/0008-teeth-are-not-treatment-areas.md

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+# Teeth are not Treatment Areas
+
+A Treatment Area is a `CatalogCategory` snapshotted onto a case, which made "one category per tooth"
+look like a free way to get dental charting. It was rejected: FDI tooth numbering is a universal fact,
+not a per-clinic taxonomy, so it would duplicate 32 to 52 identical rows into every clinic's service
+tree, surfaces would need a further level below that, and the persistent condition of a tooth — missing,
+crowned, implanted years before the patient ever arrived — has nowhere to live on a settings row.
+A tooth is instead an FDI `smallint` on the record that targets it, and tooth condition is its own
+snapshot table in the Dental context.
+
+## Consequences
+
+Tooth condition must be updated after each visit, and that projection lives in exactly one class rather
+than being spread across controllers. In exchange, rendering a chart is one query and never a replay of
+history.