PR Vision v0.3.0: per-call cost accountability + LLM call audit trail

P0 security:
- PRV_Gateway_Client: remove response body from RuntimeException (HTTP status only)
- PRV_Capture_Writer: allowlist-only write (prompt/response text, never headers/auth)
- Mandatory capture order: can_afford → probe → persist_result → update_row_cost → write_meta → capture_io
- capture_io last and wrapped in swallowing try/catch

New tables (SCHEMA_VERSION 3):
- prv_call_meta: cost/metadata per call, kept indefinitely
- prv_call_io: rendered prompt + raw response, pruned on retention window (default 90d)

New classes:
- PRV_Call_Meta_Table, PRV_Call_Io_Table: table schema + dbDelta
- PRV_Capture_Writer: metadata + I/O write; security allowlist enforced
- PRV_Prune_Cron: daily prv_daily_prune cron deletes aged prv_call_io rows only
- PRV_Cost_Rollup_Query: MTD summary, model breakdown, drill-down, projection
- PRV_Call_Log_Query: paginated + filtered call-log query + per-call I/O fetch
- PRV_Costs_Page + PRV_Costs_Renderer: Costs admin sub-page (cap progress, bento, model table, drill-down)
- PRV_Call_Log_Page + PRV_Call_Log_Table_Renderer: Call Log admin sub-page (filter bar, paginated table, WCAG AA pagination)
- PRV_Call_Drawer_Renderer: non-modal complementary drawer (5 states: Normal/Pruned/Legacy/Failed/Loading)
- PRV_Call_Drawer_Script: inline JS for drawer (300-line split from renderer)
- PRV_Call_Detail_Ajax: wp_ajax_prv_call_detail AJAX handler
- PRV_Admin_Page_Css: CSS provider (300-line split from PRV_Admin_Page)
- PRV_Probe_Run_Executor: inner probe loop (300-line split from PRV_Probe_Runner)

Updated:
- PRV_Probe_Result: tokens_in/tokens_out params + getters
- Both providers: report tokens_in/tokens_out from usage.prompt_tokens/completion_tokens
- PRV_Probe_Runner: slimmed to lock+UUID+delegation; injects PRV_Capture_Writer
- PRV_Config: get_io_retention_days(); PRV_IO_RETENTION_DEFAULT_DAYS constant
- PRV_Upgrader/Activator/Deactivator/Plugin: register new tables, cron, pages, AJAX
- Settings: retention days field + save in controller
- uninstall.php: DROP both new tables, clear prv_daily_prune cron
- Subnav 4-tab strip (Dashboard | Costs | Call Log | Settings) on all pages
- ARCHITECTURE.md, CHANGELOG.md, CONTEXT.md, CONVENTIONS.md updated

Tests:
- test-capture-writer.php: write_meta, write_io, P0 security (401 record has no key/Bearer/sk-or-)
- test-cost-audit.php: MTD reconciliation, projection, prune, forced capture_io exception, table drops

Agent-Session: peptiderepo-geomonitor-v0.3.0-cost-audit

includes/providers/class-prv-perplexity-provider.php

@@ -133,7 +133,11 @@ class PRV_Perplexity_Provider implements PRV_Probe_Provider {
 			$cost_usd = (float) $data['usage']['total_tokens'] * 0.000001;
 		}
 
-		return new PRV_Probe_Result( $raw_excerpt, $domains, $cited, $our_position, $cost_usd );
+		// Token counts for per-call attribution.
+		$tokens_in  = isset( $data['usage']['prompt_tokens'] ) ? (int) $data['usage']['prompt_tokens'] : null;
+		$tokens_out = isset( $data['usage']['completion_tokens'] ) ? (int) $data['usage']['completion_tokens'] : null;
+
+		return new PRV_Probe_Result( $raw_excerpt, $domains, $cited, $our_position, $cost_usd, $tokens_in, $tokens_out );
 	}
 
 	/**