Add an embedded systems topic

Eight conferences and six journals, curated for the computer-science side of
the field. EDA and circuit-design venues are deliberately excluded — DAC, DATE,
ICCAD and CODES+ISSS are canonical for embedded systems but not for the kind of
work this site tracks — and venues.yaml carries that rationale as a header
comment so the next person doesn't "helpfully" add them back.

Two curation calls worth recording. SenSys, IPSN and IoTDI merged in 2026 into
one conference, the ACM/IEEE International Conference on Embedded Artificial
Intelligence and Sensing Systems; it is tracked under the SenSys acronym, which
is what ICORE and DBLP still use, and IPSN and IoTDI are not listed separately.
RTCSA and ICCPS were dropped — the first is CORE B with no announced 2027
edition, the second carries no CORE rank at all.

Deadlines are all source: manual, verified against the official CFPs. Only EWSN
has a WikiCFP entry for its current edition; every other series there stops at
an edition that has already been held, so the rest are wikicfp_id: false. ECRTS
and LCTES have no announced next edition and sit under missing:, which renders
as TBD. With the stale-deadline handling from 5b06f48 this reads correctly:
only RTAS shows an open deadline, and the rest land in the elapsed-rounds table
rather than advertising passed dates as upcoming.

The topic also exposed three generator bugs that cloud-edge never hit:

_journals_section_body() read scimago_* straight off the venues.yaml entry, so
the journals index showed a dash for every journal without inline values, while
the journal pages resolved the same numbers from rankings/scimago.csv. Both now
share a _journal_ranks() helper, and gen_section_indexes() takes the SCImago
table to feed it. cloud-edge never saw this because all seven of its journals
carry inline values.

The SCImago CSV writes SJR with a decimal comma (0,864). Nothing consumed those
values before, so the loader now normalises them to a dot and CSV-derived
numbers render like the inline ones.

gen_digests() now writes digests/_index.md. Hugo only auto-creates a section
page when the section has a listable page, and a topic with no digests yet
holds nothing but build.list: never stubs, so the Digests nav link 404'd. It
preserves any existing body, leaving cloud-edge's file unchanged.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

site/content/embedded-systems/venues/conferences/RTSS/_index.md

@@ -0,0 +1,38 @@
+---
+title: RTSS
+full_name: IEEE Real-Time Systems Symposium
+domain:
+- embedded-systems
+- real-time-systems
+- scheduling
+type: conference
+icore_rank: A*
+homepage: https://2026.rtss.org/
+dblp_key: conf/rtss
+draft: false
+next_deadline: May 26, 2026
+abstract_deadline: May 21, 2026
+camera_ready: Sep 16, 2026
+next_event: Dec 8-11, 2026
+location: Yokohama, Japan
+cfp_url: https://2026.rtss.org/cfp/
+---
+
+*IEEE Real-Time Systems Symposium*
+
+| | |
+|---|---|
+| **ICORE Rank** | **A\*** |
+| **Domains** | `embedded-systems`, `real-time-systems`, `scheduling` |
+| **Website** | [https://2026.rtss.org/](https://2026.rtss.org/) |
+
+## Upcoming Deadline
+
+| | |
+|---|---|
+| **Abstract deadline** | May 21, 2026 |
+| **Paper deadline** | May 26, 2026 |
+| **Camera-ready** | Sep 16, 2026 |
+| **Event dates** | Dec 8-11, 2026 |
+| **Location** | Yokohama, Japan |
+| **CFP** | [https://2026.rtss.org/cfp/](https://2026.rtss.org/cfp/) |