docs(rustqc): tone down RustQC mentions to match experimental status

- README: prefix the RustQC bullet with "experimental" and the "trial
  on pilot data first" caveat already used in the schema
- nextflow_schema.json: drop "RustQC supersedes this tool" from the
  four QC skip_* descriptions; replace with a shorter
  "no effect under --use_rustqc (experimental)" note
- ro-crate-metadata.json: refresh embedded README description

Author: pinin4fjords

README.md

@@ -49,7 +49,7 @@
     3. [`dupRadar`](https://bioconductor.org/packages/release/bioc/html/dupRadar.html)
     4. [`Preseq`](http://smithlabresearch.org/software/preseq/) (_disabled by default; enable with `--skip_preseq false`_)
     5. [`DESeq2`](https://bioconductor.org/packages/release/bioc/html/DESeq2.html)
-    6. Or use [`RustQC`](https://github.com/seqeralabs/rustqc), a single-pass replacement for RSeQC, Qualimap, dupRadar, Preseq and SAMtools stats; enable with `--use_rustqc` (see usage docs).
+    6. Or, _experimental_: [`RustQC`](https://github.com/seqeralabs/rustqc) as a single-pass alternative to RSeQC, Qualimap, dupRadar, Preseq, and SAMtools stats (enable with `--use_rustqc`; recommend trialling on pilot data first).
     7. Contamination detection on selected screening reads (unaligned by default); _optional_
        1. [`Kraken2`](https://ccb.jhu.edu/software/kraken2/) -> [`Bracken`](https://ccb.jhu.edu/software/bracken/)
        2. [`Sylph`](https://sylph-docs.github.io/)

nextflow_schema.json

@@ -804,25 +804,25 @@
                     "type": "boolean",
                     "default": false,
                     "fa_icon": "fas fa-fast-forward",
-                    "description": "Skip dupRadar. Has no effect when `--use_rustqc` is enabled (RustQC supersedes this tool)."
+                    "description": "Skip dupRadar. Has no effect under `--use_rustqc` (experimental)."
                 },
                 "skip_qualimap": {
                     "type": "boolean",
                     "default": false,
                     "fa_icon": "fas fa-fast-forward",
-                    "description": "Skip Qualimap. Has no effect when `--use_rustqc` is enabled (RustQC supersedes this tool)."
+                    "description": "Skip Qualimap. Has no effect under `--use_rustqc` (experimental)."
                 },
                 "skip_rseqc": {
                     "type": "boolean",
                     "default": false,
                     "fa_icon": "fas fa-fast-forward",
-                    "description": "Skip RSeQC. Has no effect when `--use_rustqc` is enabled (RustQC supersedes this tool)."
+                    "description": "Skip RSeQC. Has no effect under `--use_rustqc` (experimental)."
                 },
                 "skip_biotype_qc": {
                     "type": "boolean",
                     "default": false,
                     "fa_icon": "fas fa-fast-forward",
-                    "description": "Skip additional featureCounts process for biotype QC. Has no effect when `--use_rustqc` is enabled (RustQC supersedes this tool)."
+                    "description": "Skip additional featureCounts process for biotype QC. Has no effect under `--use_rustqc` (experimental)."
                 },
                 "skip_deseq2_qc": {
                     "type": "boolean",