Update params and validations

[avani-bhojwani]

• Changed the "quant_only" param to "skip_assembly" for clarification.
• Updated param descriptions for clarity.
• Added input param validations to manage incompatible params.
• Added example output from TransRate.

PR checklist

• [X] This comment contains a description of changes (with reason).
• [X] If you've fixed a bug or added code that should be tested, add tests!
• [N/A] If you've added a new tool - have you followed the pipeline conventions in the contribution docs
• [N/A] If necessary, also make a PR on the nf-core/denovotranscript branch on the nf-core/test-datasets repository.
• [X] Make sure your code lints (nf-core lint).
• [X] Ensure the test suite passes (nextflow run . -profile test,docker --outdir <OUTDIR>).
• [X] Check for unexpected warnings in debug mode (nextflow run . -profile debug,test,docker --outdir <OUTDIR>).
• [X] Usage Documentation in docs/usage.md is updated.
• [X] Output Documentation in docs/output.md is updated.
• [N/A ] CHANGELOG.md is updated.
• [ N/A] README.md is updated (including new tool citations and authors/contributors).