fix(pages): rename _shared.lua -> shared.lua so GitHub Pages serves it

Irish transcription was returning 404 in production for
wiktionary_pron/lua_modules/ga-passes/_shared.lua, breaking the language
entirely — all 17 passes plus the engine require that module, so the first
fetch failed and nothing transcribed.

Cause: the Pages build runs actions/jekyll-build-pages, and Jekyll excludes
any path whose basename starts with an underscore. Proven in production: in
the same directory and commit, 01_polarity.lua and init.lua return 200 while
_shared.lua returns 404.

The previous attempt (9c20c06) added _config.yml with an `include:` entry for
the path. That did NOT work — the deploy ran on that commit and succeeded, and
the file was still 404, because jekyll-build-pages runs in safe mode with
GitHub's own config overrides and ignores a repo _config.yml. (.nojekyll is
likewise irrelevant: it only bypasses the legacy Pages pipeline, not an
explicit build action.) That file is removed here.

Renaming is the fix that actually holds: no underscore, nothing for Jekyll to
strip. Mechanical change — one require form, `require("ga-passes._shared")` ->
`require("ga-passes.shared")`, across 19 files. The internal `local _shared`
variable is untouched; it is just an identifier.

Note for future syncs: the source repo
(wiktionary_ipa_phoneme_lexicons/irish/passes/) still names the module
_shared.lua, since it never goes through Jekyll. Syncing is therefore no longer
a pure `passes.` -> `ga-passes.` rewrite — it must also map `_shared` ->
`shared`.

Verified locally: golden 81 pass, transcription e2e 13/13 pass. Production
verification requires a redeploy.

Author: hellpanderrr

_config.yml

@@ -2,7 +2,7 @@
 -- Replaces the monolith irish_engine.lua + irish_rules.lua.
 -- Loads passes from passes/ directory and orchestrates them.
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 local passes = require("ga-passes.init")
 local ustring = require("ustring.ustring")
 local ulen = ustring.len

wiktionary_pron/lua_modules/ga-irish_engine.lua

@@ -3,7 +3,7 @@
 -- References: Hickey II.1.1 (polarity system), III.2.3.2 (lenition mutation outcomes),
 --  FG Ch.5 (Connacht consonant inventory)
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 return {
   name = "polarity",

wiktionary_pron/lua_modules/ga-passes/01_polarity.lua

@@ -3,7 +3,7 @@
 -- Runs early so vocalization (pass #6) and reduction (pass #11) are stress-aware.
 -- References: Hickey II.3 (stress), FG Ch.5 (Connacht stress patterns)
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 local MONOSYLLABIC_STRESS = {
   ["ailm"]=true,["airg"]=true,["aoibh"]=true,["aoir"]=true,

wiktionary_pron/lua_modules/ga-passes/02_stress.lua

@@ -7,7 +7,7 @@
 -- so multi-word eclipsis (i bhfad, i dtosach) works.
 -- References: Hickey III.2.3.1 (nasalisation / eclipsis), Hickey III.2.2.2 (T-prefix), FG Ch.7 (mutation mapping)
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 local ECLIPSIS_PAIRS = { mb = true, gc = true, dt = true, bp = true, nd = true, nn = true, bhf = true }
 

wiktionary_pron/lua_modules/ga-passes/03_eclipsis.lua

@@ -3,7 +3,7 @@
 -- ortho is what the fricative rules see.
 -- References: Hickey II.2.2 (cluster simplification), II.2.1 (permissible clusters)
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 return {
   name = "cluster_simplify",

wiktionary_pron/lua_modules/ga-passes/04_cluster_simplify.lua

@@ -5,7 +5,7 @@
 -- References: Hickey II.1.7.2 (lenited fricatives — dependent phonemes),
 --  Hickey III.2.3.2 (lenition — grammatical mutation), FG Ch.7 (mutation outcomes per dialect)
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 return {
   name = "mutated_fricatives",

wiktionary_pron/lua_modules/ga-passes/05_mutated_fricatives.lua

@@ -5,7 +5,7 @@
 -- after consonants have been resolved by pass #9.
 -- References: Hickey II.1.9.9.1 (vocalisation of fricatives), II.1.9.4 (vowel gradation)
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 return {
   name = "vocalization",

wiktionary_pron/lua_modules/ga-passes/06_vocalization.lua

@@ -6,7 +6,7 @@
 -- Runs after r_lowering (#6c), before labial_vocalization (#6e).
 -- Uses orthography to check, since vowel resolution hasn't run yet.
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 return {
   name = "anticipatory_raising",

wiktionary_pron/lua_modules/ga-passes/06d_anticipatory_raising.lua

@@ -4,7 +4,7 @@
 -- Runs after vocalization so vocalized forms aren't re-nasalized.
 -- References: Hickey II.1.9.4 (vowel gradation — nasal raising before geminate sonorants)
 
-local S = require("ga-passes._shared")
+local S = require("ga-passes.shared")
 
 return {
   name = "nasalization",