HFC245fa concentration constraint column missing 'fa' suffix in SSP CSVs

[shyamperi]

Summary

The C++ source registers the HFC-245fa concentration-constraint input as
HFC245fa_constrain. Every SSP CSV that ships under
inst/input/tables/ exposes the column as HFC245_constrain (missing
the fa suffix). Same CSV uses the correct HFC245fa_emissions for
the emissions column — so the inconsistency is within a single header.

Effect: setData of HFC245fa_constrain from a CSV-backed binding
silently fails to find a matching column. Constraint never binds.

Reproduction

$ git checkout 9631b05f6e139303436c48c9d80ebb8425e88708   # v3.5.0 commit

$ grep -n 'D_CONSTRAINT_HFC245' inst/include/component_data.hpp
170:#define D_CONSTRAINT_HFC245fa HFC245fa_COMPONENT_BASE CONC_CONSTRAINT_EXTENSION

$ grep -n 'HFC245fa_COMPONENT_BASE' inst/include/component_names.hpp
...:#define HFC245fa_COMPONENT_BASE "HFC245fa"

# CONC_CONSTRAINT_EXTENSION is "_constrain", so D_CONSTRAINT_HFC245fa
# expands to the string "HFC245fa_constrain".

$ head -7 inst/input/tables/ssp245_emiss-constraints_rf.csv | tail -1 | tr ',' '\n' | grep HFC245
HFC245fa_emissions    <-- correct "fa" suffix
HFC245_constrain      <-- BUG: missing "fa"

Reproduces in all 9 SSP CSVs (ssp119, ssp126, ssp245, ssp370,
ssp434, ssp460, ssp534-over, ssp585, picontrol).

Proposed fix

Rename the column from HFC245_constrain → HFC245fa_constrain in
every SSP CSV in inst/input/tables/. Matches the C++ constant + the
existing HFC245fa_emissions column in the same header.

If the CSVs are regenerated by JGCRI/hectordata rather than maintained
by hand, the fix lives in hectordata's generation logic — likely a
column-name list using HFC245 where it should use HFC245fa. Happy
to file in hectordata instead if maintainers prefer.

Why "fa" is the canonical form

HFC-245fa is the IUPAC-style designation for 1,1,1,3,3-pentafluoropropane;
the trailing fa isn't optional — it disambiguates from other
pentafluoropropanes (e.g. HFC-245ca, HFC-245eb). The C++ uses the
canonical form (HFC245fa everywhere); the CSV column is the typo.

Impact

• Direct: Users can't constrain HFC-245fa concentration via the
  standard CSV path. Workaround: rename the column locally + add an
  .ini binding pointing at the renamed column.