Refactor/perf batch 10

[timcadman]

What's changed

Aside from the standard refactor:

• isValidDS / .checkDisclosureSize: isValidDS(x) now takes a name, for the client. The old logic moved unchanged into the internal .checkDisclosureSize(obj), which server functions that already hold the object call directly (replaceNaDS, quantileMeanDS, rowColCalcDS, recodeLevelsDS).
• tableDS force.nfilter / exclude: these are literal values, not object names, so they're converted directly with no .loadServersideObject. NA in exclude now always means missing; before, it only did when it was the sole value.
• lexisDS2 carried-forward variables: built by loading each name, reproducing data.frame()'s column naming (D$var → D.var). Checked identical to the old eval(parse()) output.
• lexisDS2 entryCol = NULL: now defaults entry times to 0, as documented. It never worked before.
• getWGSRDS: numeric only, and thirdPart is checked only for bfa, both matching the old client check.

[StuartWheater]

Fixing setting ot PERF.PROFILE env variable", hoping it will be complete in 10min.