docs: note DMARC RFC support in the features list (#778)

* docs: note DMARC RFC support in the features list

The features list only mentioned "draft and 1.0" aggregate reports. Spell
out the standards parsedmarc parses: RFC 7489 (legacy DMARC) and the final
DMARC standard RFC 9989 with RFC 9990 aggregate reports, RFC 6591 and
RFC 9991 failure reports, and RFC 8460 SMTP TLS reports.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: align Python compatibility table pipes (MD060)

The emoji cells were padded for display width, leaving the source pipes
misaligned by character count and tripping markdownlint MD060. Re-pad so
every row's pipes line up by codepoint.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: list all optional output destinations; fix table emoji alignment

Expand the features list to cover every output sink: Elasticsearch,
OpenSearch, Splunk, and PostgreSQL (premade dashboards), plus Kafka,
Amazon S3, Azure Log Analytics (Microsoft Sentinel), Graylog (GELF),
syslog, and HTTP webhooks.

Also re-pad the Python compatibility table using display width (the
status emoji render two columns wide), which is what markdownlint MD060
measures — the previous codepoint-based padding still tripped the rule.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: separate PostgreSQL from the premade-dashboards clause

PostgreSQL is a storage target without bundled premade dashboards, so it
shouldn't sit inside the "for use with premade dashboards" phrase next to
Elasticsearch/OpenSearch/Splunk.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: move PostgreSQL to the non-dashboard outputs line

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: use compact markdown tables

Switch the markdown tables (Python compatibility, env-var section mapping)
to compact single-space format. It reads cleanly in a text editor and
sidesteps the column-alignment churn that emoji/variable-width content
caused with padded tables (markdownlint MD060). The reStructuredText grid
table in dmarc.md is left as-is — it relies on multi-line cells markdown
can't express.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/source/usage.md

@@ -714,24 +714,24 @@ then read and stored as the `credentials_file` value.
 
 For sections with underscores in the name, the full section name is used:
 
-| Section          | Env var prefix                |
-|------------------|-------------------------------|
-| `general`        | `PARSEDMARC_GENERAL_`         |
-| `mailbox`        | `PARSEDMARC_MAILBOX_`         |
-| `imap`           | `PARSEDMARC_IMAP_`            |
-| `msgraph`        | `PARSEDMARC_MSGRAPH_`         |
-| `elasticsearch`  | `PARSEDMARC_ELASTICSEARCH_`   |
-| `opensearch`     | `PARSEDMARC_OPENSEARCH_`      |
-| `splunk_hec`     | `PARSEDMARC_SPLUNK_HEC_`      |
-| `kafka`          | `PARSEDMARC_KAFKA_`           |
-| `smtp`           | `PARSEDMARC_SMTP_`            |
-| `s3`             | `PARSEDMARC_S3_`              |
-| `syslog`         | `PARSEDMARC_SYSLOG_`          |
-| `gmail_api`      | `PARSEDMARC_GMAIL_API_`       |
-| `maildir`        | `PARSEDMARC_MAILDIR_`         |
-| `log_analytics`  | `PARSEDMARC_LOG_ANALYTICS_`   |
-| `gelf`           | `PARSEDMARC_GELF_`            |
-| `webhook`        | `PARSEDMARC_WEBHOOK_`         |
+| Section | Env var prefix |
+| --- | --- |
+| `general` | `PARSEDMARC_GENERAL_` |
+| `mailbox` | `PARSEDMARC_MAILBOX_` |
+| `imap` | `PARSEDMARC_IMAP_` |
+| `msgraph` | `PARSEDMARC_MSGRAPH_` |
+| `elasticsearch` | `PARSEDMARC_ELASTICSEARCH_` |
+| `opensearch` | `PARSEDMARC_OPENSEARCH_` |
+| `splunk_hec` | `PARSEDMARC_SPLUNK_HEC_` |
+| `kafka` | `PARSEDMARC_KAFKA_` |
+| `smtp` | `PARSEDMARC_SMTP_` |
+| `s3` | `PARSEDMARC_S3_` |
+| `syslog` | `PARSEDMARC_SYSLOG_` |
+| `gmail_api` | `PARSEDMARC_GMAIL_API_` |
+| `maildir` | `PARSEDMARC_MAILDIR_` |
+| `log_analytics` | `PARSEDMARC_LOG_ANALYTICS_` |
+| `gelf` | `PARSEDMARC_GELF_` |
+| `webhook` | `PARSEDMARC_WEBHOOK_` |
 
 ## Performance tuning