feat: dbt-managed Snowflake semantic view for prospect funnel

[benjamin-shi-tql]

Summary

Deploys the prospect funnel metrics as a native Snowflake SEMANTIC VIEW (YARDI.MARTS.SEM_PROSPECT_FUNNEL), with the DDL controlled from this dbt repo. This is the Snowflake-native alternative to the MetricFlow YAML approach (PR #5) — the metrics become a real Snowflake object consumable by Cortex Analyst and SEMANTIC_VIEW(...) queries.

Pattern: control model + post-hook macro

dbt has no native SEMANTIC VIEW materialization, so:

• models/semantic_views/sem_prospect_funnel.sql — one-row anchor model that ref('fct_prospects') (forces build order) and carries a post_hook.
• macros/create_prospect_semantic_view.sql — holds the CREATE OR REPLACE SEMANTIC VIEW DDL; runs on every dbt run.
• models/semantic_views/_sem_prospect_funnel.yml — docs/tests.

Semantic view contents

• TABLES: prospects over fct_prospects, PK prospect_id, synonyms.
• FACTS: toured / applied / approved / leased flags + days_to_apply / days_to_movein + desired_rent.
• DIMENSIONS: prospect_status, lead_source, desired_bedrooms, leasing_agent, property_name/region/fund, contact_date/month (with synonyms).
• METRICS: total_prospects, leased_prospects, tour_rate, application_rate, approval_rate, lead_to_lease_conversion, avg_days_to_apply, avg_days_to_movein, avg_desired_rent.

Validation (live Yardi (Demo))

• DDL grammar confirmed against Snowflake CREATE SEMANTIC VIEW docs.
• Connector is read-only, so the object is created by dbt run; metric math validated by reproducing every metric on source data: 150 prospects, 19 leased, tour_rate 0.613, application_rate 0.547, approval_rate 0.415, lead_to_lease_conversion 0.127, avg_days_to_apply 7.4, avg_days_to_movein 34.1, avg_desired_rent 2221.

Consuming

SELECT * FROM SEMANTIC_VIEW(
  YARDI.MARTS.SEM_PROSPECT_FUNNEL
  DIMENSIONS lead_source
  METRICS lead_to_lease_conversion, total_prospects
) ORDER BY lead_to_lease_conversion DESC;

Depends on fct_prospects (PR #4). Supersedes the MetricFlow YAML in PR #5 if you prefer the Snowflake-native route.